Baffled Oil Pans Explained

Story and Photos by Matthew Eddy

Outside View of Baffled Oil Pan for 5.0L Mustang

Normal production cars have what is called a “wet sump” meaning the majority of the oil is stored within the oil pan.  A pick up for the oil pump is located in the oil pan and sucks the oil up to lubricate critical areas within the engine.  This system is used because it is simple and cheap to manufacture and is more than sufficient to meet the needs of the commuter consumer.  However, in motorsports the car and engine are going to be subjected to high g-forces for an extended period of time which the wet sump system may not be able to cope with.  For example, in a long continuous high g turn, the oil will slosh to one side of the pan away from the oil pick up.  No oil gets sucked up and starves the engine which leads to excessive wear and catastrophic engine failure in a pretty short period of time. 

The best method to prevent oil starvation is to go with a dry sump system.  This is used in pretty much all the top racing series cars such as Formual 1, NASCAR, Indy, and American Le Mans.  There is an oil pan but it has a very limited capacity and the sump pump basically sucks all the oil out as fast as possible and stores it in a oil reservoir the is external to the engine. Oil pressure is maintained by feeding the oil from this external oil tank back into the engine so the engine is never wanting for oil.  An added benefit of this system is since the oil pan is very low profile, the engine can be lowered to lower the cars center of gravity.  Unfortunately these systems are very expensive.  A bargain basement pump will run you at least $800 and could run upwards of $2000.  Not to mention a new, possibly custom, oil pan, lines, oil reservoir and more. 

Most weekend warriors can’t justify a dry sump system especially if you are just a track day junkie who doesn’t really have a prepped car but there are a couple lower cost alternatives.  One is to get or make a baffled oil pan.  This will limit how much the oil able to slosh around and hopefully keep it where the pump can suck it up into the engine.  Simply put a baffled oil pan will has chambers that make it easy for the oil to travel toward the oil pick up but difficult for it to get sloshed the other way. Also, they tend to increase the capacity of the oil pan so that more oil will be available in the whole system. 

Below you can see a picture of a Ford Racing baffled oil pan out of a 5.0L Mustang.  This one is used mainly for drag racing but the concepts are the same between drag and road track with some design differences to account for lateral acceleration (g-forces experienced while cornering).  

Baffled Oil Pan from a 5.0L Mustang

You will notice the oil pan has two compartments, a shallow on the right side of the picture and a deeper one on the left.  The reason for the compartment on the right (which is the front of the engine) is to allow space for the oil pump.  The hump that separates the two compartments is required to clear the front cross member that goes under the engine.  In the left compartment is a square chamber that that is designed to trap oil and that is where the oil pick up is located.  At first you may be wondering why is seems to be cordoned off, but what is difficult to see in the picture above are the trap doors that only open inward to allow oil to enter the chamber but not exit (see picture below).  A few other features to note are the lips at the top of the chamber and also one on the left side of the center hump.  These lips prevent the oil from splashing up and out of the camber.  The pan is designed such that for the oil to travel from the left or right side of the pan (up and down in the picture), it must pass through the oil pick up chamber where it will be trapped.  

Baffles in Oil Pan

Above you can see a close up of the baffling in the oil pick up chamber.  The doors can only open inward which will allow the oil to enter but not exit.

Oil Scraper in Mustang Oil Pan

The feature pictured above is called a scraper.  As the crank spins, beads of oil are flung around the inside the engine.  The scraper catches most of these to prevent the oil from going up into the cylinders and instead returns it to the pan.  


In the near future I plan to make one of these for my V6 MR2 and when I do so, I will be posting a "How-To" article.

How-To: Coil-Over Conversion
Story and photos by Matthew Eddy

Over the last year I have slowly been prepping my 91 Toyota MR2 for NASA (National Auto Sports Association) Time Trials and eventually race in the Performance Touring series.  Last summer I swapped in a 3.0L V6 and over the winter I have built and installed what I am calling a coil-over conversion; converting the stock struts to coil-overs. 

What may not be clear to all my readers is what coil-overs are and what benefits they bestow over struts since they seem very similar.  If you are purchasing a coil-overs, especially good ones, you are pretty much guaranteed that the dampers and the springs are going to be well matched.  Secondly, coil-overs allow for ride height and corner weight adjustments.   Also they have common spring sizes so it would be easy to swap out springs to fine tune the suspension for individual tracks or if you make other modifications.

Measure First

Before doing this conversion check and see how much clearance you have between the front wheels/tires and the strut housing.  On the MR2, the front spring sits above the wheels and the strut housing is only 1/4" from the wheel.  In most cases you will need to either get new wheels with a larger offset or wheel spacers.  I installed 12mm spacers and new longer wheel studs.  Replacing the wheel studs is pretty easy, especially if you have an impact.  I have posted a video on youtube that shows how to do it here.  I bought both teh studs and spacers on ebay.  To find the spacer search for "hubcentric MR2" and they are usually priced at about $60 pair.  The wheels studs were $35 for 10pcs.  Also, keep in mind that you will need to get new front end-links with this conversion because the bracket is being relocated.  You can deal with this one of two ways; buy Powergrid Endlinks which can be ordered at custom lengths (you will need 5.5" center to center), or cut and weld the stock ones but the stock ones are probably so old and rusty you are better off getting new ones anyways.

Powergrid End links.  It might be hard to believe, but these aren't new, they have been on my car for 2-3 years.

Next, measure your current ride height for baseline for future adjustments after installing the coil-overs.  Park the car on a level surface and measure from the ground, through the center of the wheel to the lip of the fender.  Also measure from the center of the hub to the fender lip.  If you have any fender damage or rust that might make these measurements unreliable pick another point to measure to.  WRITE THIS DOWN, or at the very least, text message yourself.  You will want this information later.

New Studs and 12mm Spacer.

Strut Preparation

The following write up is specific to the MKII MR2 but is still applicable across many makes and models.  One major difference you may encounter is that many cars cannot take strut cartridges.   In the MR2, I can remove the actual damper from the strut housing itself but I do not believe this is a common feature.  If you find this is the case with your struts you have one of two options.  Convert the strut to accept the coil-over sleeve or convert the strut to accept cartridges.  I will address this a bit more at the end of the post since my suggestions will make more sense after you see what is involved.

It might be a good idea to buy an old used set of struts to work on that way if you mess them up some how or the project is more involved than you anticipated you can take as much time as you need.

Strut Diagram - parts of the strut.

Strut Diagram - Distances to measure

See the diagram to the left as a reference for the terms I use for the various parts of the strut. 

1. Disassemble the strut and remove the upper mount and spring.  Second, take measurements.  See my video posted on youtube that shows how to disassemble struts HERE. Reference the diagram on the right.  

2.Measure the overall length of the strut, the length of the body, the distance from the end links bracket to the end of the strut (if applicable) (G or F or both), the shock body diameter (A),  length of the strut rod (D), the diameter of the strut end (B), and distances to other brackets you may have on the strut body.  Also measure the length of the spring, and the thickness of the upper strut mount.

MR2 Struts in Before Being Disassembled.

Disassembled Struts with Spring Perches

3. Cut off the spring perches and grind the housing "smooth."  For the MR2 front strut you will also need to cut off the sway bar end-link bracket.


3a (Optional) - To convert struts that don't usually take cartridges you can convert them to cartridges by drill a small hole near the bottom of the strut to relieve the pressure, then cut off the top of strut to remove the guts.

Disassembled Struts with Spring Perches Cut Off.

Struts Close-up; Spring Perches Cut Off. You can see the gland nut just above the grounded down area.

4.  Put the strut housing into a vice and remove the gland nut with a monkey wrench.

Removing Gland Nut From Strut.

5.  For the front struts, weld the front sway bar bracket just above the knuckle bracket.  Then weld a bead around the strut for the coil-over sleeves to sit on.  For the rear struts, the sleeve will also sit on the sway bar bracket, and you should weld a bead around the strut at that location. 

Weld a bead around the struts for the coil-over sleeve to sit on like this.

6. Cut the bump stock bump stop in half.   More than likely you will be lowering the car which means you will be decreasing the travel of the shock so cutting the bump stop in half will give you a little more travel.

7. (Optional) Sand blast and paint the strut housings.  I would also suggest grinding off any sharp features.  That will reduce the chances of the paint chipping or peeling.  For instance there are little tabs on the knuckle bracket that should be ground down.  After painting them, us caulk or silicon to fill in the gap around the top of the knuckle bracket.  This will prevent water and debris from collecting there and causing corrosion in the future.  I used a special caulk that is applied before powder coating (see the second picture below).

Stock Struts Sand Blasted.

I Have Applied Caulk to the Above Area.

Strut Assembly

I have compiled parts list with prices so you can have an idea of what you need and how much it will cost.  I have not included the cost of the struts or dampers (aka shocks).  For certain parts I have included links to where you can buy them. 

Parts List:

Coil Over Parts - (Left to right) Gland Nut, Lock Nut, 1" Washer, Strut Cartridge, Strut Housing, Top Mount, o-ring (center of pic), Coilover Sleeve, lower Spring Perch, Upper Spring Perch, Spring.

Coil-over Sleeves; 2.038" ID, 5" Length (x4): $15.53 ea

Lower Spring Perch (x4): $12.60 ea

2.5" Coil Spring Tops - Upper Spring Perch(2 sets): $64 total (with powder coating)

Springs – Fronts (Set of 2) (Eibach, 250# 8”): $103 – bought as Edelbrocks on Summit Racing

Springs – Rear (Set of 2) (King, 400# 10”): $43 – bought on ebay, used

O-rings (8 total): $4 (local hardware store)
18mm Washer (6): $2 (local hardware store)
1" Washer (2): $1.50 (local hardware store) 
Light Weight Oil (engine oil, shock oil): $4 (local autoparts store)
Total: $334

Part List Notes:

Spring Rates: Not sure which spring rates to use?  Check out my blog posting about choosing spring rates HERE.  For my MR2 - which I drive to a from the track/autoX, I choose 250 in/lbs front, and 400 in/lbs for the 

Coil-over Sleeves:  I used 5" sleeves because I am using sway bars and that's probably as low as you can move the front sway bar bracket.  I would not suggest going sway barless because there might be a time that you actually want a sway bar.  Also you shouldn't need to get more than 5" of travel that I can think of.  However, on the rears, you can move the sway bar bracket down 2" and get a 7" soil-over sleeve.  

2.5" Coil Spring Tops:  You will need to measure the diameter of the strut cylinder and the guy will customize the inner diameter for you.  I would also suggest getting the parts powder coated to protect them from debris.




Assembly


1. Put (1) o-ring on the strut housing (about 2-3" from the top of strut housing)
2. Slide coil-over sleeve over o-ring.  The sleeve should slide over the o-ring and be moderately tight.  If the o-ring is just to thick, wrap the strut tower with electrical tape about 1" above the weld bead.  The purpose of the o-ring or electrical tape is to remove play between the sleeve and the housing and prevent the sleeve from spinning when adjusting ride height. 
3. Take a second o-ring and force it into the gap between the strut housing and sleeve from the top. See pic below.

Using a flat head screw driver to insert o-ring.  Here the gland nut is already on, but its a lot easier to do this before installing gland nut.

4. Screw the lower spring perch onto sleeve (can be done later).
5. Put the strut housing into a vice, and protect the paint with rags.  Pour about 3oz of oil into the housing.  The oil fills the gap between the cartridge and the strut housing to prevent heat building up in the shock.  I prefer not to use tranny fluid or gear oil because of the smell.  I used some engine oil because it was convenient.
6. Insert strut cartridge.  Check oil level, and fill as necessary.  You want the oil to be about .5-1" from the top.
7. Apply some anti-seize to the gland nut and screw it on.  First by hand and then tighten with a monkey wrench.
8. Put spring on. 
9. Put bump stop on the shock cylinder.
10. Put top spring perch on
11. Put (1) 1" washer on (FOR THE FRONT STRUTS ONLY).  This is acting as a spacer so that the top spring perch contacts the bearing portion of the front strut mount.  See below photos.  I also added bearing greases here to prevent corrosion and wear.  This section will be turning with the wheels.  Though I have two pictures, each showing a washer, you only need to use one washer.  The pictures below are just to demonstrate where the washer will sit. 

Washer sitting on spring top.

Where the washer will sit on the strut mount.

12. Put the strut mount on.
13. Put (3) 18mm washers on (FRONT ONLY).  The stock upper strut mount would usually sit under the mount and without it there is some play between the mount and the locking nut that holds this all together. 
14. Screw on the locking nut on the end of the shock shaft.  The hardest part about this is that the shock will want to spin.  You best bet it to snug it up by holding the shaft with your fingers through the coil.  Once it starts to spin you can try wrapping a piece of rubber around the shaft and grip it with vice grips.  Get them as tight as you can.  Don't worry, you won't be able to get it super tight, but it should be good enough. 


When you are done they will look something like this.

Coil-over Conversion.  Fronts for a MKII MR2 with 10" springs.  I later switched to 8" springs.

Here is a pic of them mounted in the car.

Front Coil-overs mounted on the cars.

For struts without gland nuts you can weld on the strut without removing the inner shock but take a few precautions such as welding in short durations.  Do not weld weld near the valves (toward the top or bottom of the strut). But the better option will be to cut off the top of the strut, remove the damper and then weld a threaded collar that will allow you to swap out strut cartridges.  You will probably have to do some research and find a cartridge that is the proper diameter and length to fit. 

Adjusting Ride Height

 When I installed mine I moved the lower spring perch up to hold the spring against the top mount, then mounted the coil-overs on the car.  Measure the ride height from the ground to the fender as described above.  Remember to do this on a level surface!  If, by magic or math you got the ride height perfect on the first go then make sure everything is tightened up and take it for a test drive.  If you want to make adjustments then jack up the car, remove the wheel and measure the distance from the lower spring perch to some point on the strut.  Then adjust the position of the lower spring perch to change the ride height. Below you can see how I measured using a metric measuring tape.  I find metric to be much easier than figuring out what fraction of an inch I was looking at. I was using the knuckle bracket as my reference point.  In this cse I was at 73mm.  I wanted to reduce my ride height by 1".  25mm = 1" so to lower the car 1" I need to moved the lower spring perch down until I measure 48mm.
 
 

Measuring the Distance of Lower Spring Perch to Reference Point on Coil-Over.

Sure enough, I dropped the car and I was at exactly where I wanted to be.

If you have questions, please feel free to ask them in the comment section below.  


Fine Print: You are responsible for your own safety and modifications to you car.  I am not responsible for any damage, injury or death that may result.  Follow these steps at your own risk and if you aren't sure you are doing something safely then don't do it. Always use proper safety equipment.  Modifying or changing existing products on your car is risky and not suggested by the manufacturer so any damage, injury or death is your own responsibility.  Do not attempt if you don't feel you can accomplish this safely.  Make sure to check all the bolts are tightened properly and test the car before driving it.

How to Choose Spring Rates

Spring Rates Calculator

Using Suspension Frequency to Help Determine Ideal Spring Rates for your car.

In the right margin of this blog I have posted a spring rate calculator.  It looks like a small excel spreadsheet and it will help you determine what spring rates will work best for your application.  Most consumers who are upgrading their suspension don’t think about spring rates they choose a coilover kit or brand of springs and bolt them on.  They may be basing their decision on opinions or reviews they read online and they may not be getting the best setup for their application.  When I say most consumers, a large majority of consumers are modding their cars for cosmetic reasons and aren’t actually intending to participate in any motor sports.  So for them, the spring rate is inconsequential because they are looking for either a good brand they can brag about or something that is inexpensive.  

If, on the other hand, you are interested in actually participating in some sort of motor sport like AutoX, track days, or racing, then a properly tuned suspension will give you an advantage over your competitors who may have only bought a recommended coilover package.  This isn’t necessarily a bad way to go since there are a lot of good coilover kits out there that are tuned for the car and application.  But understanding spring rates and how they can be used to custom tune your suspension to very specific tracks or your own driving style can give you an edge on the competition.  At the very least it will give you a better understanding of how the suspension works. 

You don’t need coilovers to adjust spring rates, but one advantage of coilovers is that the springs have a standard diameter and you will be able to find a variety of spring rates and lengths online.  Usually the rates will be available in 50lb increments.  This gives you much better suspension tuning options than an aftermarket spring kit that is designed to fit the stock spring locations.  These kits are cheaper since you don’t need to upgrade to coilovers but there won’t be a variety of spring rates available to choose from.

The standard spring rate measurement I will be using is lbs per inch which represents the amount of force in pounds it takes to compress a spring one inch.  For example a 400lb spring will compress one inch when 400lbs of force is applied.  The same spring will compress two inches when 800lbs are applied and four inches when 1600lbs are applied.  To give you some perspective a Ford Focus might have 80-150lb springs, a mildly built Miata might have 300lb springs and a full track car may have 600-2000lb springs.  Obviously the higher the spring rate the harder the ride. Bigger cars will also have stiffer springs since the springs will have to carry the weight of a heavier vehicle.  

It seems obvious to many why stiffer springs would be more desirable, but it may not be obvious to everyone.  A brief explanation is that a stiffer spring maintains to road contact, the car won’t lean as much in a turn, and it won’t bow as much under heavy braking.  The compromise is that the ride quality will be much harsher and that means less comfortable for daily driving. This will be covered in more detail in future articles.

Suspension frequency (SF) describes the natural frequency of the spring in relation to wheel motion and can be used to estimate the appropriate spring rate for various applications.  The calculation isn’t particularly difficult but will require either finding data or taking measurements of the car.  You can also use this to evaluate spring rates of various coilover kits and stock spring packages.  Most passenger cars will have a rate of approximately 1 Hz.  A fairly aggressive suspension setup will be around 2.0 Hz and a track dedicated car will have a frequency of around 3.0 Hz or more.  So you can use this information to figure out where on this spectrum of suspension frequencies will fit your application.  If you drive your car to the track or AutoX event you might want to try a SF a little over 2.0.  It is important to note that you want your rear SF to be slightly higher than your front otherwise the car might start to porpoise; rock forward and backward.  Also keep in mind that you will need to upgrade your dampers (aka shocks) to handle springs that are stiffer if you haven’t done so already, especially if you choose a very aggressive spring rate.   

The spring rate calculator on the right is fairly simple to use.  Figure out what suspension frequency you want, update the vehicle data for your car in the white cells and the ideal spring rate will update in the yellow.  Everything in gray should be left alone and the calculated spring rates will be yellow.  For now none of the cells are protected so you could go in and modify any of them but none of the changes will be permanent.  If you make any mistakes, refresh the page and it will reset the calculator.  The spring rates are calculated for individual corner of the car but since the left and right side should be essentially the same the calculator will only calculate front and rear. If you want some more background information check out the Eibach website.  Please note for a live axle or solid beam axle this calculator will not work.

User Inputs:

Race Weight - This is the weight of the car with fully suited driver, and fuel.  If the car is stock, take the curb weight, add your own weight when fully suited, and a little extra for incidentals.

Weight Distribution Front - percent of the total weight of the car in the front.  You can use stock data to get you close.

Unsprung weight - this is the weight not supported by the springs, so this is the weight of the wheels, tires, hubs, brake caliper, half the control arm, etc.  You can estimate this weight and it will probably be somewhere between 80-100lbs per corner.  Keep in mind that particularly large wheels will be significantly heavier and may push your unsprung weight well over 100lbs per corner.  Since some cars have staggered wheels the unsprung weight from front to rear may be very different.

Spring Angle - if you have a McPherson Strut, you can estimate the angle at 5-10 degrees.  Otherwise you need to determine what angle from vertical the spring/coilover/strut is mounted in the car. 

D1 & D2 - D1 is the distance from the spring mount on the control arm to the control arm pivot point. D2 is the distance from the ball joint to the control arm pivot point.  The units aren't important as long as they are the same (mm, inches, feet, furlongs or whatever). If you have a McPherson strut, then leave these numbers alone since 98/100 is the approximate ratio.  You will see you need to do this for the front and rear.  If you are a Mustang owner and have a live axle, just do it for the front since this is not setup for solid axle setups. 

Everything in gray should be left alone since it is either calculated for you based on the info you entered in the white cells or cell descriptors but I will explain what the various measurements are.

MR - Motion Ratio, this is the ratio of the motion of the wheel to the motion of the spring.  This is calculated by taking D1 and dividing it by D2.  That is why the units of measure aren’t important, since we are using them to calculate a ratio.

ACF (Angle Correction Factor) - This is needed to accurately calculate the how much the spring compresses in relation to the wheel motion.

Front and rear Sprung Weight - In this formula, this is calculated based on the weight distribution and unsprung weight.  In this current configuration, the unsprung weight is considered to be the same for front and rear wheels.  I will update it shortly so that you can put unique values for the front or the rear.

Spring Rates - These are the required spring rates to achieve the desired suspension frequency.  You probably won’t be able to get a 212.3356 # spring, so you will have to decide if you want to with a 200# of 250# spring.  When deciding which way to go, remember that you want the rear SF to be slightly higher than the front, so look at both the front and rear SF before deciding. 

If you have any questions please feel free to leave a comment, and feedback would be appreciated.

Myth of Big Brake Upgrades

Lemans Car at Sebring - the red glow within the wheels are the rotors heating up in a braking zone just before a turn. Photo by Jeffery Ling

It is easy to believe that larger rotors and bigger calipers will make your car stop faster, but that is because most people assume that brakes stop the car, when in actuality they only stop the wheels.  This may seem like a minor distinction, but consider this: if you slam on the brakes and lock up the wheels (assume the car doesn’t have ABS for simplicity), does the car stop?  Not when traveling at speed it doesn't.  The car slides for a while with smoke billowing  and the tires screaming in agony.  At this point, stopping distance is determined not by the size of the rotor, or if they are cross-drilled, or Carbotech brake pads, but by the tires.  A quick side note: locking up the tires is never considered to be the fastest way to stop a car, but even still, it’s the tires that will have the biggest impact on the stopping distance of a car.

So, if the brake system only stops the wheels from turning, but doesn’t stop the car, then why use fancy drilled and slotted rotors, the $150+ race pads, and multi-piston calipers?  The answer is a bit more complicated and will require a short and hopefully painless foray into the world of physics.  The brake system of a car is an energy conversion system. It takes the energy of the car’s momentum and converts it to heat.  When you apply the brakes you slow down because your forward momentum is being converted into heat energy by the friction of the pads on the rotors.  If you slam on the brakes once, the car will slow down very quickly and your brake system will become very hot. If You then accelerate and do it again within a short time interval the brakes get hotter.  And if  you keep doing this, eventually you will put so much heat into the system that they don't work effectively any more, and the brakes will feel softer and softer until they don’t work any more.  This is called brake fade.  For those who have lived or driven in the mountains are already familiar with brake fade when descending a mountain.  If you haven’t had the chance to drive in the mountains then let me explain.  When heading down hill for an extended period of time you are constantly checking your speed with some braking inputs to keep you from accelerating.  If you don’t down shift and take some of the load off the brake system your brakes get so hot that they don’t work any more, and then your trip down the mountain becomes rather terrifying.  It is when you are stressing the brake system with repeated accelerating and hard braking like you would on a road track that a big brake system makes sense. 

Here is a list of common brake upgrades and what purpose they serve.  You will notice almost all of them deal with managing heat or increasing the heat tolerance of the system.

DOT 4 or 5 brake fluid – Most cars come with DOT3 brake fluid, which is perfectly fine for every day driving, but DOT 4 has a higher boiling point so the fluid can withstand higher temperatures so the brakes can get hotter before they start to fade.  I would highly recommend using at least DOT 4 in any track car.  DOT 5 is silicone based and has an even higher boiling point, but the brake lines need to be thoroughly flushed when converting a DOT 3/4 system to DOT 5 since the different fluids do not play well together.

Stainless Steel Brake lines – Brake lines in the car tend to be all hard lines except for a short flexible rubber section from the chassis to the caliper to allow for suspension travel.  When the brakes fluid heats up from heavy use, the rubber gets a little softer and allows the line to expand a little, which translates into a slightly softer pedal feel.  The stainless steel lines don’t allow the line to expand and so the brakes feel a bit stiffer and more consistent.  Also, the stainless steel is much more durable.

Racing Compound Brake Pads – If you go to your local auto parts store for pads they cater to the common driver who aren’t racing their car and don’t want noisy brakes.  The primary difference between a race formulated pad and an AutoZone pad is that the compound works at higher temperatures.  Because of this, many of the really aggressive race pads will need to come to temperature before becoming 100% effective.  You will also notice a big difference in feel.  The brakes should feel sharper, will be more consistent.  They also tend to be noisier, and its very important that they are bedded in before taking them out on the track.  There may be additional benefits to give up an arm or a leg for the more expensive pads depending on application.  My 24 Hours of Lemons team runs a ‘96 Neon, and at our first race we ran Hawk Blacks.  After approximately 8 hours of racing the pads were worn out, and the backing plate bent backwards cracking the caliper piston.  We had to swap not only pads but scrounge for another caliper, which we ended up taking off another team’s car that had retired with a blown engine. I am not blaming the Hawks, they are good pads, and we believe that a major cause for the failure was lack of airflow to the front brakes.  However, we installed brake ducts and now run Carbotechs that cost over $200 just for the fronts, because they have a good track record for surviving an endurance race, and they have an extra thick backer plate to prevent the pads from bending backwards, because this is a common problem with Neons.

Slotted Rotors – A slotted rotor has grooves machined into the face of the rotor that helps give the pad a bit more traction and vents gases that are produced as the pad heats up. This will wear the pads faster but should have a sharp, and more importantly, a consistent feel.

Cross-Drilled Rotors – As I had mentioned, a lot of hard braking in a short period of time will cause heat to build up in the brakes, and if they get hot enough the braking power becomes less and less, until it eventually fails all together.  These rotors will have holes drilled into them that will help the rotors cool down faster so that the brakes don’t fade.  There are also the combination rotors that have been both drilled and slotted so that they have benefits of both.  Please do not go cheap on these parts, since a cheaply made cross drilled rotor can crack prematurely and potentially fail at a very inconvenient time.

Larger Rotors –Having a larger rotor means there is more rotor material and they can absorb much more heat energy.  Also they have more surface area so they will cool faster.

Multi-piston Calipers – Many of you may not even know what a caliper piston is so I will try and briefly explain.  The caliper is a hydraulic system that squeezes the pads against the rotors.  To do this there is a cylinder that one of the pads sits against, and when the brake pedal is pressed, the piston presses it against the rotor.  An arm on the caliper assembly that moves with the pressure of the piston reaches over the rotor and applies braking pressure to the other pad on the opposite side of the rotor.  In general, this one piston system works fine because it is more than sufficient for street driving.  However, on the track the system is being taxed heavily, and as the brakes heat up the pads will flex slightly.  The single piston in the middle of the pad will focus the brake pressure on the center of the pad and the edges will flex away from the rotor.  This means the pad is not being heated evenly and so the whole pad is not sharing in the braking load.  Arranging multiple pistons behind the pad means the braking force is more evenly applied for increased braking efficiency.  There are dual piston, 4 piston, and 6 piston calipers that I am aware of.  Since more of the load is being shared along the whole length of the pad, they don't wear as fast and can actually save you money as well as improve safety.

Brake Ducts – These are a very simple modification that can really improve the effectiveness, and life, of your brakes when on the track.  There are special brake ducting hose that looks like plastic dryer ducting, or you can be really cheap and just get aluminum dryer ducting.  The idea is to route some air from the front of the car to the rotors so that they stay cooler.

When I was running my MR2 track car, I had run the stock brakes with stock pads and had no issues with brake fade, and I definitely can lock up the wheels, so the only modification I made was to run DOT4 brake fluid.  But the car only has a 135 horse power, so its no rocket ship, and therefore I wasn’t putting a lot of heat into the brakes.  I have just recently swapped in a V6 which has increased my WHP from 100 (in actuality, the motor was pretty tired, so I bet I was closer to 85 or 90) to about 165.  Though I haven’t run the car yet, I am anticipating that I will have issues with the stock brakes overheating.  The plan is to upsize the brakes to what the turbo model has and add stainless steel brake lines.  Since the turbo has approximately 200hp, and my V6 version has about the same, the cars braking requirements should be about equal and so this upgrade should be sufficient.

How to Upgrade Smartly
Racing, or even tracking, a car is an expensive hobby, so you may be wondering how to get the most bang for your buck when upgrading your brakes.  One easy rule of thumb is that if you have modified your car, giving it significantly more horsepower, then it is a good bet that you will also need to upgrade the brakes before you take to the track, since the stock system probably won't be able to handle the extra heat.  Another indication that you will need to make some modifications to your brake system would be if you are experiencing brake fade while on the track, even if it is a stock car running stock brakes. 
First, always upgrade your brake fluid to at least DOT 4.  In order for this to be effective you need to bleed brake lines dry but you won't have to flush them.  While you are at it, I would suggest getting the stainless steel brake lines for the extra durability and better pedal feel.

If you are only experiencing slight fading when on the track a pretty simple and relatively cheap modification would be to add brake ducts.  Sometimes all you need is a bit more air flow to keep the brakes cool and they will be fine.  

If you have done both of these and are still experiencing brake fade it's time to look at new rotors and pads.  There are mildly aggressive race pads that will handle heat better than regular stock pads.  Cross-drilled rotors shed heat a lot faster than the plain-Jane rotors that come with most cars, so the combination of the two should give you a significant improvement.  
Finally, if none of this is working you have a pretty serious car or a mechanical issue.  Serious cars means big brakes, which means new rotors, calipers, and pads.  This is a pretty involved upgrade, since this can also effect your brake balance, which is a whole other discussion.  

Of course, if you are ever having braking issues on the track, slow down to a safe speed and pit.  Also, when in doubt, either about making any modifications to your car or the safety of the car you should always make the safe decision.

How To Inspect Your Car For The Track

For your safety and the safety of other participants, it is important that you bring a car that is mechanically safe for the track.  There will likely be some sort of safety or tech inspection, but no one will know the car as well as you, so ultimately, it's your responsibility to make sure that the car you are bringing to the event is safe.  If you aren't the mechanic in the family I would suggest learning the basics like changing a tire, torquing the wheels, checking fluids and bleeding brakes.  It isn't uncommon to have to bleed the brakes while at the track because you cooked your brake fluid.

- Fluid leaks:  Look for any significant leaks and get them fixed.  If the engine is wet from oil, but its not dripping significantly, you will be OK.  Significant leaks are anything that leaves a quarter sized puddle after the car has been sitting for an hour.  This is transmission, engine, radiator, brakes, power steering, fuel (want to burn to death?), differential, blinker fluid and any other fluids your car may have that I forgot about.

- Brakes: Check to make sure your rotors are in decent shape and you have plenty of meat on the pads. Even if the fluid looks good and you have good pedal feel it's still a good idea to bleed the brakes to get some fresh fluid in the calipers.  If you change pads then you should bed in the brakes to give you the best possible braking performance. It is also a good idea to bring an extra set of pads in case you wear out the current set on your car.

- Suspension/drive-train.  Check for any loose components especially ball joints, tie rods, wheel bearings, and control arms.  One way to check it is to grab the top of the tire with the car on the ground and shake it.  If there is play or funny noises, you better investigate further.  Then jack up the car, and grab the tire in the 3 and 9 o'clock position and shake it.  Then repeat in the 12 and 6 o'clock position.  Again, you are looking for excessive play or noises that indicating that there are some loose parts.

- Tires:  You should expect to wear the tires pretty significantly, so check them for thread depth, uneven wear, cracking, cuts or damage.  Check them between sessions to make sure you still have meat on them, but I wouldn't recommend going to an event unless the tires have at least half the thread depth left otherwise you might have to retire from the event early.

- Battery:  It must be secured so that it doesn't become a wrecking ball inside the car.

- Wheel Torque.  Bring a torque wrench to check the lugs regularly before, during and after the event. Know what you should be torquing your lugs to because if you over do it you can break wheel studs which the organizers won't like to much.  Plus, think how embarrassing it would be if a wheel came off on the course.

- Steering:  I should feel tight.  Older cars with the conventional steering linkage may have more play, but if its excessive you need determine if you have any worn components.

-Misc:  Safety belts need to be functional.  Tail lights usually need to be functioning.  The inside of the car needs to be cleared of loose items, including the floor mats. No cracks in the windshield. No loose or hanging body panels. No significant rust in structural areas of the car such as the frame, suspension hard points, and strut towers.

Just figure that you could be going 100+ mph into a turn, do you want a mechanical failure to send you into the wall?  If the answer is yes, then please let me know which track day you will be at so I can avoid it.  When in doubt, slow the car to a safe speed and return to the pits and ask someone to help you.  There are a lot of cool people out there, and they will be more than happy to help if they can.  Track days are the most fun when you go home with your car and your self in one piece, so don't worry about getting your moneys worth. 

How to Track Your Car

When I say "track" I mean a road track.  With turns. Right as well as left hand turns.  Usually in some interesting configuration.  So I am not talking about drag strips, speedways, or circle tracks.  Road tracks would be like Watkins Glen, Laguna Seca, or anything that Formula 1 races on.  A road course tests the car and driver as a whole, not just acceleration or top end speed, but also cornering, braking and car control. 

It might surprise you how easy it is to be able to get your car out on real race track by participating in an event called an Open Track Day (OPD), also known as a High Performance Driving Event (HPDE).  It is like actual racing but mitigating the risk by limiting how and when cars can pass each other.  Generally this means you can drive your car as close to the limit as you feel comfortable, but you can only pass a slower car on the straights after they have pointed you by.  Sure, sometimes you can get stuck in "traffic" but usually the events are organized in such a fashion as to give you plenty of track time, so the few laps in which you are working through slower cars, you can make up for it with many more open laps and pushing yourself and your car.

Now you might be asking what do you need.  For the car, it should be in fine running order.  Some tracks may require convertibles to have a roll bar, but you won't need a roll cage, race suit.  Just a regular old Ford Taurus would be fine.  Maybe not fun, but a stock car is perfectly acceptable.  I will define what "fine working order" means in more detail a little later.  Cost wise, registration fees can range anywhere from $100-400/day depending on how nice the track is and who is organizing it.  For instance, Laguna Seca is about the $300-400 range, where Gingerman Raceway in South Haven Michigan is about $150.  Gingerman is a nice track, but it doesn't have the pedigree of Laguna Seca.  Your next biggest expense, unless you already have one, would be a helmet and that can cost $250 or more if you want a really fancy one.  Next would be gas.  Not only for driving to a from the track, but also at the track and that expense will vary with the car.  If you have a helmet, and you go to Gingerman, then you can expect to pay about $350 for the day if you are driving 4 or so hours to the track and staying at a hotel for one night.  If you can camp on the track, I would suggest it since it usually means you can walk the track the night before and perhaps even make some friends with other drivers.

Step one; find the nearest tracks.  You may be lucky and live in the Detroit area in which there are 5 tracks within a 4 or 5 hour drive or you may live in a race track desert and will have no choice but to drive 8+ hours.  Unfortunately if you try searching on google maps you can get a lot of false positives, but its a good place to start.  One really helpful website is Trackpedia.com.  On that site you can browse tracks by continent, region and state so you can then easily identify tracks that might be close to you, see the course layout, see in-car video of the track and read through the turn by turn guide.  Once you have identified some local or not so local tracks, you can find their website and see if they have a posted schedule for open track days or what groups are hosting events there.  For instance, you might see that the Porsche Owners Club has an event, and they may be open to anyone who might be interested in attending simply because they can't can't get a large enough group from within the club to cover the costs of renting the track.  Also, there are groups that all they do is track events such as 3Ballsracing.  If necessary, you can always try and contact the track and see what groups are around that allow random people to attend.

Hopefully you have found a track and some potential track dates it's time to get ready.  You need inspect the car for potential mechanical issues that if not addressed or identified might make the day a little more dramatic than you originally intended.  I will post a write up on how to check your car before you bring it to the track.  If you don't feel comfortable doing it yourself, you can bring it to a mechanic who can do it for you.  Whoever is organizing the track day may have a few local mechanics that they would suggest.  It is better to address any problems ahead of time because the organizers will likely have a safety (aka tech) inspection on site to try and identify and mechanical hazards.  And if your car is deemed as being unsafe, you may not be able to run.

Besides having a car in fine working order, you will need a helmet.  When purchasing a helmet you should pay attention to teh safety rating since different tracks or organizations may have different requirements.  When in doubt a SNELL SA2010 full face helmet will meet or exceed all requirements and you can use it if you start racing.

Most importantly, bring an open mind.  Listen to people.  If available, ride along with more experienced drivers.  Take it easy, and try and work on the fundamentals; racing line, identifying turn in points and getting a feel for the car. Of course, have fun, and you won't be having fun if you are pushing to hard, driving stupidly and crashing. 

Lastly, keep in mind that you will be at the track all day, and it will probably be hot.  Try and get plenty of sleep the night before because you will definitely get more out of it if you aren't hungover or half asleep.  Bring sunscreen, a hat, a chair, some shade if you can, a cooler with drinks to keep hydrated (preferably water),and snacks.  Don't under estimate how much your performance on the track will be dictated by how dehydrated, hungry or fatigued you will become from the heat.

See my next post on inspecting and prepping your car for the open track day.

Review: 2011 Honda CR-Z

It has been about 14 years since Toyota unleashed the Prius on the world.  From the motorsports crowd it garnered a nod for innovation but also instilled a little fear since hybrid cars seemed to foreshadow the eventual doom of car racing as we know it.  I am sure many were imagining a world where little electric cars whirred by so quietly the crowds could drown out the sound with their own collective breathing.  Perhaps that future may still await us, but there is another chapter to be told that will be belted out in the raucous breath of fossil fuels and I think the opening line is the humble little CR-Z

It really is the first affordable sport hybrid.  When I first saw it at the North American International Auto Show in Detroit, Porsche was releasing the 918 which is a super hybrid that only costs $845,000.  That is expensive even by super car standards.  These aren’t the first two sports hybrids.  Over the last couple years and in various racing series, a few hybrid race cars have been fielded, including the Kinetic Energy Regeneration System (KERS) employed in Formula 1.  Like the hybrid technology found in regular road going cars, the KERS system is charged by capturing some of the energy that would be lost during braking.  This hybrid technology adds a little spice into F1 since the driver now has a "turbo" button that he could press to give him 80 extra horses for up to 6 seconds per lap.  Of course the system adds weight, it's tricky to tune without throwing off the brake balance, and there have been reliability issues.  Now that F1 is in the second season of implementation after taking one season off in 2010, many of the teams have worked out the bugs and it will become more refined as time goes on.  What I find most fascinating about the CR-Z is that Honda was able to bottle what is essentially the same technology, and sell it for less than $20,000 USD.

I am not saying this car is a monster on the street; far from it.  The little 1.5L engine puts out a whooping 112hp with 107lbs of torque with a manual tranny; one more of each over the CVT. However, this is combined with an integrated electric motor that kicks in when you are accelerating to give you an additional 14 horses and 58 lbs of torque at 1000-1500 rpms.  Which means the little bugger is quite peppy! 

This car really is the grandson of the CRX; it’s a two seater economy car that is really only a sports car in that it’s light enough to seem fast with that tiny engine, and has the stance and look of a sporty car.  What is really nice is how the whole drive train is packaged.  The batteries aren't huge since they aren't intended to power the car on their own, so they don’t add to much weight.  The electric motor is about the size of a pizza and is sandwiched between the engine and trans. When the car knows you are accelerating, the electric motor kicks in to help the engine like a mini supercharger.  Honda has dubbed their hybrid system the Integrated Motor Assist (IMS) and was already employed in the Insight.  The most amazing part of the car is it offers us a glimpse of the future.  Take a moment and imagine this technology scaled up into a true track thrasher.  A Civic SI with 200hp from a 2.0L engine coupled with the IMS that improves gas mileage, and gives the car significant torque off the line.  Or instead, what if this was implemented into the anticipated Toyobaru where 250+ hp wouldn't be overly ambitious for a RWD car as it might be for the FWD Civic.  That car would be a real monster.

Well, enough of this envisioning what this car promises for the future; what is the car like?  I will keep is pretty short, since I have spent enough time talking about how this car is the pivot point for a new chapter in motorsports.

On The Street

I like.  It makes a nifty commuter, and if I was looking to buy another daily driver, it would be in the top 5 cars I would consider because it is pretty fun to drive.  It gets pretty good gas mileage; 35 city, 39 highway. The six speed manual tranny is smooth and easy to use, though the gears are pretty tightly packed.  The seats are comfortable and I really liked how the dash was laid out.  My only critique of the interior is that the air conditioning knob was exactly where I expected the volume for the stereo to be.  Every time I tried to change the volume, I adjusted the air conditioning fan speed.  As you would expect, everything was plastic, but seemed solidly built. 

It has all the standard features you would expect in a car built for the MP3 generation.  A small cubby hole in the center console has a USB cable to plug in a thumb drive loaded with music.  There is also an auxiliary input jack on the face of the stereo.  In the standard model there is a 160 watt stereo, which can be upgraded to 360 watts in the EX car.

Taking a queue from some fancier cars, the CR-Z has three driving modes; Sport, Normal, and Econ.  In sport mode the throttle response is sharpened, the steering is tightened up, and the electric motor is used more aggressively. Even in this mode with the manual transmission, if you come to a stop and you are in neutral, the engine will turn off until you up it into gear.  Then the electric motor kicks the engine back on.

When in Econ mode, and driving the manual, the car will reduce the use of accessories and use the electric motor to maximize efficiency.  However, with the CVT tranny, the car will shift sooner to keep the rpms low and therefore the gas consumption low as well. You will get better fuel economy with the CVT than you would in the manual but I think the manual would be more fun to drive.  So if you are just driving to work, then you run in Econ mode.  You decide you want to race a Civic off the line at a light, then hit the Sport button; which you can do on the fly.

Many complain about the visibility, and it has two main blind spots.  Looking out the back of the car, the hatch frame blocks much of the view and the c-pillars are so wide that there is a bit of a blind spot in the rear quarters.  Yeah, those are annoying, but I think you would get used to it.  For me, there is one major drawback and really makes me hesitate to buy one; the safety rating for this car is only 3 stars for front and side impact.  Yeah, in rollovers it is rated at 5 stars, but considering that if I did buy this car it would primarily be a commuter car and perhaps secondly an autoX'er. I am more worried about hitting other idiots on the road or them hitting me than I am about rolling over.  So I would feel a bit better if Honda put 50-100 pounds of steel in the car to reinforce the body and perhaps bump its safety rating to 4 or 5.

For the Track

This car would be slotted into the "fun but not terribly fast" category; even with 122 combined horses of the combustion and electric motor working in unison.  Sure the car is peppy, but it goes from 0-60 at the same pace as my girlfriend's Fit.  Even it if isn't really faster than a Fit, the suspension and chassis are MUCH MUCH better.  The CR-Z 5" shorter, 2" wider and has a lot better road feel especially with the bucket seats that come standard.  Its track credibility is enhanced by the 4 wheel disc brakes, but I almost wonder if they are necessary.  With a 58.8 to 41.2 weight distribution, I don't know how much stopping the rear wheels will be doing when the car leans forward under hard braking.

Overall I would be happy to own the car, but given the abundance of large trucks on the American roads, I would be a little worried about getting tagged by some wayward driver. It would probably be a fun autoX'er and it gets good gas mileage but I would doubt that it would make a fun track car for the intermediate or experienced driver.  However, I do like that it gives us a preview of what affordable sporty hybrids will look like in the near future.

Specs:

Hp: 122hp combined

Weight Disp: 58.8/41.2

Weight (lbs, MT/CVT): 2637/2690

Track Car for the Novice

It’s easy to find a lot of articles about which car is the best track car, but they are usually measuring which car can turn the fastest lap time.  That is really good for experienced drivers, but what about the best track car if you are a first timer?  I thought it would be good to do a write up on what the best novice track car would be.  If you are interested in really honing your skills so that you can drive a car at or near its limit on a track or would like to get into racing, then please sit down with an open mind and let me explain my philosophy before you just peruse the list to see where your car falls.

Whenever I talk to someone about tracking a car they always assume that a car needs to be modified.   Why?  I guess many assume that when taking a car out onto the track it should be prepped for the track with power and suspension mods, but most cars that you would want to take to the track will be just fine in the stock form.  Adding power and suspension modification only adds another layer of complexity and obscures the skills a novice driver should be focusing on.  Watching track and race videos can be very deceiving since you really don’t get a good feel for how fast those corners seem to come at you, how hard to turn, and then there are the walls, the little bumps, and the slip angle of the tires.  A friend of mine summed it up in one word: scary.  It’s a fun scary, but you won’t really know what I mean until you have done it.  Even now you are probably thinking “I am going to tear the track up!”  Basically if you really want to be a skilled driver then put on the training wheels.  It seems that every hobby I have pursued, there are the foundational skill sets that when mastered will make it easier to concentrate on practicing the advanced skills.  So with this in mind, I have a few suggestions on what is the best way to learn to drive a car at speed on a track.  Of course, always be safe.  You aren’t going to become a great driver if you crash and burn.

Try AutoX (pronounced auto-cross) first.  Not glamorous, but it is fun.  One benefit is that the courses are set up to try and limit the possibility of you wrecking your car if you spin or otherwise make a fool of yourself.  But really the best part of autoxing is that you can get a feel for the car in a relatively safe setting.  Don’t make excuses that the events are “confusing with all those cones” or some BS like that.  Try it.  When you do, really push the car.  Try and make it spin.  Try and brake really late and hard.  Practice threshold braking.  Feel how hard you can corner.  What does the car do when you take it into a corner to fast?  What happens when you give it to much throttle in the middle of the corner?  There shouldn’t be any hard obstacles or people out there to hit if you totally push wide in a corner or spin.  When I make new significant modifications to my car I like to thrash it around at an autoX first just to see how the car feels and it gives me more confidence when I got to the track that if I do spin I have some idea what I need to do to recover.

I will assume that you probably already have a car, and that is the car you intend to track.  However, if you don’t have a car yet or want to buy another car, I have compiled this list of cars from Ideal to Terrible.  Now I wish that I could have driven all these cars, but I haven’t so some of this is based on the tech sheets or second hand knowledge but I wanted to list most of the popular models.  It’s important to note that one assumption I made with this list is that the cars are NOT MODIFIED or have minor modifications such as intake, exhaust, sway bar change maybe some newer slightly adjustable suspension.  So no turbo upgrades, no coilovers, no aero.

Ideal Cars - These cars will all share common characteristics; front engine, rear wheel drive, low powered. Why these characteristics?  Most high powered race cars are going to be rear wheel drive and since those cars are going to be prone to oversteer, you should learn to control it and use it.  Sure a lot of high power cars are going to be mid-engine, but mid-engine cars can be difficult to learn in because when they start to spin, they spin fast where a front engine car has more progressive oversteer, that’s easier to detect, correct for, and recover from.  Now, the most important part is you want a low power car so that you can concentrate on fundamental driver skills such as racing lines, smooth down shifts and car control without having to do it at 100+ mph.  Trust me, like I said earlier, it may seem like the faster the better, but once you actually do it, it’s better to start slow, learn the fundamentals and then step it up to the fast cars.  Remember, training wheels before the ten speed.

Mazda Miata (base model, no forced induction)
Mazda RX-7 (old models that aren’t turbocharged)
Toyota Corrolla (83-87 AE86, RWD car)
Pontiac Solstice (no turbo or supercharger)
Saturn Sky (non-tubro of course)
Nissan 240SX, 300Z
Porsche 944 (non turbo)

Good Cars - These cars are fun and will help the novice driver learn to drive a track, but may not have handling characteristics that emulate the typical race car or higher end sports cars.

Honda Civic, Accord, Fit, CRX
Dodge Neon (DOHC or SOHC versions, not the SRT4)
Acura Integra (not the Type-R)
Nissan Sentra (normal or SE-R)
VW Golf, Scirocco, Corrado, GTI (no VR6 or turbos)
Ford Focus, Escort, Fiesta
Chevy Cobalt (not the SS of course)
Subaru 2.5RS, Legacy, regular Impreza
Mini Cooper

Marginal Cars – These cars are rated as such mostly because they are a little fast to make the Ideal or Good list, though a couple mid-engine cars made the marginal list since they have well tuned suspension or low power so that they aren’t to much of a handful.

Ford Mustang
Chevy Cobalt SS
BMWs
Dodge SRT-4, Challenger, Charger
VW R32, VR6’s
Toyota Supra (Mark 2&3), MR2 Spyder (’00-’05)
Nissan 300ZX (non-turbo)
AudiA4, TT
Porsche Cayman, Boxter, 944 Turbo
Fiat X1/9
Nissan 350Z & 370Z

Mazda RX-8

A Little Scary – Handling characteristics are tricky or speed is just getting to fast to make them a good novice car. For instance, the mid-engine layout has some very solid advantages, but they also can be very “snappy”, meaning that when the tail end breaks loose and starts to spin, it will do so quickly and the driver needs to be very attuned to the car to be able to catch it.

Chevy Corvette, Camaro
Toyota MR2, Supra (Mark 4)
Lotus Elise
Subaru WRX or STI
Mitsubishi EVOs
Porsche 911 (non-turbo)
Nissan GT-R

Terrible – Keep in mind this is for a novice driver.  Don’t misinterpret this list; all of these cars make great track cars but not if you are trying to learn.  Basically, take all the super cars and lump them into this class, but here are some particularly difficult to drive:

Porsche 911 (especially the older ones)
Dodge Viper
Ariel Atom