It's breaking down/thinning out and leaking out of every diff on any FD I take to the track.

When I drain it, it's that nasty dark stinky fluid that has been over heated.

A lower rear end is great through all the gears (cheap power/torque). At some point I'll also put in a lower 5th to help acceleration in 5th gear.

PS The diff gets super hot so no way can you touch it even after 20 minutes of cooling down.

Thanks for the info!
Andrew

Nice Vids! what do you like running for your alignment specs with your setup? thanks

If your diff temps are that hot you need an oil cooler and electric pump to keep the temp down and save your diff

Very happy for you Frtiz. Awesome video. When watching you I always feel like I am watching something that is playing at 2X speed :)

I think you described your driving as a teenager on Red Bull, with the twitching and constant moving. I call it flat out fast as I clocked a few of your laps at the 2:04 or so mark. Good stuff. Weird not seeing Oak Tree.

1/16 toe (total) front, 5.8 caster, 2.4c

zero to a little in the rear 2.4c

Thanks for the tip :icon_tup:

Thanks man!

Yep, my wife actually came up with that one. However as you know the car is in a constant slide from start to finish of every corner and without the quick open, open, open of the wheel (twitching) it would spin, if it's in control you are not going fast enough if it's out of control it's just right :nod: Of course I can be smoother (have better balance) which is the catch 22 of going fast or it's hard to go fast and be smooth etc.....I'll repeat; you will NEVER get fast without the car being out of control and it's really difficult to be smooth with an out of control car, suffice is to say being smooth is really easy if you sunday drive it and you'll look like a real pro behind that wheel (in an endurance race lol) but your lap time won't be as impressive.

For a 2.03 lap check the 3:30 mark (start finish line on the back straight for the south course which was a fairly open lap) forward to 5:33 :icon_tup:

This is an example of a pro driver in a car and it's anything but smooth. One of my favorite drivers:

Fritz, maybe you could try some liquid Teflon on that diff cover drain plug?

Here is a problem. 9.5 wide wheels and 275 width.

Wheels 101
1) Wheel width is the most important thing for speed.
2) rigidity is more important than weight.
3) Fit tire with a slight stretch to improve mechanical grip.

You are leaving a TON on the table in terms of speed with your wheel selection.

Right now you are muffin topping your tires and having poor response/mechanical grip.

I would run 275/35/18 on a 17x11 wheel. +45mm offset. weight, doesn't matter all that much as long as its under 23lbs.

You will be SO much faster. Based off the width difference, I am guessing about 1.5 seconds on a minute lap.

Another good tip :icon_tup:

I of course have 12 SSR comp 9.5 plus 42s LOL

I did try the 275 35 17 hoos but other things were off like alignment etc... so it wasn't a fair test/comparison.

As far as I know those are the only tires in that size and they are $$$ at 300 plus each. Just bought 8 c51 275 40 17 for 179 each (on sale because they are old from 2010 but seem ok).

No doubt with some cash invested I could improve my lap times :nod:

PS I also don't think a 17 x 11 plus 45 would fit under the car? The setup I have now is really tight.

I know blueTII fit a 18x11 with +45mm offset with stock rear trailing arms. He is running a 295/30/18 tire with rolled fenders front and rear.

The Optima challenge winner last year was a 65 Vette running 315/30/18 tires on 18x12 wheels, the tread width on those are 11.7" and he put them on a 12" wheel. He beat the whole field with a 65 vette;)

the tread width on a hoosier 275 is about 10.3" or so, so you could run a 10.5" wide wheel and do pretty well.

Brian Hobough won the challenge with his Vette, he also has a camaro that wins autoX events and he runs massive wheels on that as well. The key is the wheel width and stretched tires, he has his cars dialed in.

I understand, big wheels and tires are a huge piece of going fast :)

At one time I ran the standard 18 x 10 285 30 18 but the tires are 500 more. Too bad Hankook doesn't make that size.

Still can't figure out how a 17 x 11 plus 45 will fit either front or rear but especially front. A 17 x 10 plus 50 is a tight fit.

Just a note.

A "9.5" wheel is a measurement from inside bead to inside bead. Typically, you want to run the tire on the widest wheel you can within it's published range (9" to 11" for a 275/40/17), but 9.5" is the standard rim on which most manufacturers mount a 275/40/17" tire to publish measurements.

Hoosier shows a 10.3" tread width on that tire, so the tire will (does) sit pretty square on a rim that's actually more like 10.5" to the outside of the rim. Not optimal, but certainly not "mushroom topped" or problematic.

Finding a nice, light 17x10.5 or 11 wheel with the right offsets wouldn't exactly be easy. And I wouldn't say weight doesn't matter—there's a big difference in how a car feels and how the shocks work on a car with a 16 vs. 23 lb wheel. And, there's a diminishing return if you can't lower the car or set it up like you'd like to keep it from rubbing.

Yep the setup I have isn't complete muffin top but it's certainly not ideal.

One thing all us car builders/track guys can relate to is every decision we make is giving up one thing to get another even if it's just dollar bills :lol:

I think I could fit a plus 50 10.5 and will look into it. CCW can basically make anything you want you just have to pay for it hehe.

Currently I'm having the cage redone (already wasted 2200 there) and a diff cooler installed so budget is already extended/blowing up.

Any wheel sponsors out there :D

just wanted to add a small tidbit on the wheel situation . Like Fritz I went with a 17inch wheel instead of an 18 because the price on the tires is a whole lot better in that size LOL , But Finding wide wheels in 17s is quite difficult . I also ended up with a 9.5

BUT this is just my observation .. SEAT TIME > 1 inch of wheel .

Need to watch this vid when I get home.

Rate of thermal expansion for Al is roughly 2x that of Carbon Steel. I would be afraid of tightening the steel plug (if it's taper thread) while hot because when the aluminum cools down it will shrink more and there may be some very high stresses induced in the cover. Don't want to crack it!

If the cooler doesn't do the trick (I can't imagine it wouldn't) one complicated option would be to have the diff cover tapped for straight thread, turn a groove in the head of a hex head plug bolt and use a viton o-ring. I thought about an Aluminum drain plug, but Al on Al might have issues with galling/losing threads.

Yes, it is the standard width measured. but you want to basically stick to the wider range of the widths. A good rule of thumb is a wheel width, bead to bead, to be wider than the tread width.

Michelin engineers make this claim in their porsche presentation.

Slide 34 and on
www.cb-racing.com/PilotCup_Presentation.PPT

they are basically saying that running a 245/40/17 tire on a 9.5 wheel will provide less understeer, more grip from a mechanical stand point and provide better feedback and turn in.

Urge designs who sets up s2000's and their findings.

URGE designs



From Yokohama themselves
Custom Performance Tires | Yokohama Tire Corp.

High Performance Wheels


Wide Rims

If you're opting for high-performance tires, you'll probably want to include some new wheels to enhance both appearance and performance. To assure the right fit, you'll need to make sure that you've got the proper replacement wheel size, dimension and load-carrying capacity.

Narrow Rims

Result in an improvement in ride quality, but may sacrifice some of the tire's ultimate performance capability.


Increase your vehicle's stability, steering response and cornering capability. A Yokohama quick tip—use a rim width which is 90% as wide as the tread width of a performance tire for street driving. This will provide a good balance between performance and ride quality.

Mid-Range Rim Widths

Provide a balance between handling capabilities and ride quality. The wheel's width influences handling and ride quality. Always choose a rim width within the range of the tire's acceptable rim width specification.

Great info, will apply it at some point :icon_tup:

Just dropped the car off yesterday for the cage redo and diff cooler so hopefully that will do the trick.

Cool idea on the drain bolt and will definitely use that idea if it coninues to leak despite the cooler. One thing is for sure though the leaking is directly related to the fluid heating up and thinning out. I've yet to have one leak the 1st session out.

Nothing will make you faster than seat time and obviously the greener you are the more it pays to just drive and continually push your limits :nod:

With that said though these cars are 20 plus years old so they do take serious prep for even a beginner to safely go to the track but IMO stuff like coilovers, wheels, tires, brakes, turbos etc...etc... should take a back seat to simply going to the track and DRIVING!

Fritz, what fluid/viscosity are you using?

75 140 synth

Most the TT folks around me (and myself included) are using something heavier, like Amsoil 250:

AMSOIL Severe Gear® SAE 250

Might be something to try.

75-90? I'd like to give this a shot as well:icon_tup:

hah , I would guess you are quite a bit passed the whole green thing , and could probably make use of 1/4 inch of more contact patch ! That CCW idea actually sounds great! in the long run I think it would be cheaper to pay more for a wider 17 wheel . then go with an 18 and pay more for tires ! :icon_tup:

Definitely couldn't hurt but once the cooler is installed I should be good to go with 75 140