smgC32

We finally broke the 1:36 barrier this week at WSIR. We ran consistant 1:35's with a best for the day of 1:35.02. Track temps were hot and we were running 91 octane. On a colder day, I think we could have been in the 1:34's. The car is finally set up for serious track duty. The additional of the KMac front and rear camber bushings and a few washers to shim out the struts has provided enough negative camber to finally allow even tire wear accross the tread. The Nitto NT-01's are superb in 245 40 / 275 35's and due best with 40 - 42 lbs hot. We have tried them at mid 30 hot as well as 45 - 52 hot. We finally figured out cold temp for this track. 24 left front, 28 right front, 28 left rear, 30 right rear. This car is so front heavy that there is a 16 - 18 lb increase in temps in the front. The Nitto's also offer outstanding grip under braking. Finally a tire that can keep up with the Stop Tech's. We ran the Falkens again for the last session for comparison and they were better suited for greasing a baking sheet, and almost six seconds slower. We also didn't mind the addition of a Recaro SPG racing shell which kept us upright and comfortable. Not bad on the street as well if you can get into them. I'll post some pics later. I think the Quiafe LSD was good for at least a second if not more, keeping power oversteer very controlable and at a minimum when driving at this pace. Now if I just could figure out how to get that 320mm steering wheel to fit!

splinter

Congratulations. That is an outstanding lap time for our lowly W203 chassis. That's hauling some serious speed.
All those years of your hard-earned R&D have come to fruition. Nice work!

spr

pics???

splinter

Sean;

His post said .."I'll post some pics later"... Give him a break for his fine brakes, okay?
And for all the other hardware he pioneered to make it happen. Major kudos to smgC32!

smgC32

Thanks for the complements. It has only take four years to tame the beast. There is nothing left to do except buy another car and begin the process all over again!

Carl AMG

SMG - I am running NT-01's in the same sizes on my Boxster S and I just e-mailed Nitto for some guidance on hot tire pressure targets. Their answer was consistent with your findings:

"A good starting point for pressure with the NT01 is to try to achieve a hot pressure of 40 psi. The optimal temperature range for the NT01 is 160 to 220 degrees F."

Congrats on "taming the beast."

Carl

Zeppelin

SMG- sounds like you have some enthusiasm again with the car. I am amazed that the Nitto's are 6 seconds a lap faster than the RT-615's. They must be at least 10 seconds a lap faster than my T1-R's. I might feel better about my car if I can run 10 seconds quicker.

CynCarvin32

Not exactly Zepp.... we were actually saying your tires seem better than the 615's and the T1-S were even better than those. The 615's are just total rubbish and I dont know who could use those for performance driving.

His enthusiasm about the car may be short lived. He says its now fast and can be tracked so its time to sell it! Logic in that is unclear to me but hey who am I to make comments!

But you should come out again. We want to break down into the low low low 1:30's at the streets next time out so lets get a streets day set and you can come chase in the CRX!

Vadim @ FD

Good times guys!!!

I think the best time we were able to do were in 1:37s on Dunlop Race tires. But lack of diff made a huge pain in the rear coming out of the corners. Car would literally smoke inside tire making it look like we lost a motor.

smgC32

Here are some pics. The SPG seat is awsome. I have used these seats for over 15 years and for me there is no better as a dual purpose seat. When driving in this seat, you don't even think about holding yourself upright and can concentrate on driving. The wing on the left does rub though on the piller and this seat is wider than the Pole Position. The air/fuel guage is excellent and with software costs over 400.00! But it is very accurate and was helpful in understanding what the actual ratio was under load. At idle, it's at factory 14.7. Under partial load, between 12 and 13.5. And at full throttle, it runs about 10.0+/-. This RENNtech chip is tuned very well. Dyno results on various dynos show very inaccurate air/fuel ratios. And for those of you who have heard me complain about how bad the pedal configuration on the car is for the last four years, here is the final bespoke production set which is fantastic. The dead pedal is twice as wide allowing proper left leg placement, and the gas pedal is significanlty wider on the left, allowing quick foot work between it and the brake without much right leg movement, and proper heal and toe to smooth out the heavy braking downshifts, taking it easy on the transmission.

Zeppelin

I would find it hard to beleive a T1-R is faster than an RT-615. The T1-R was rated as one of the worst tires as far as grip and lap times go. The RT-615 was near the top. Granted a 615 is not a R-Compound, but it has to be better than my crappy toyo's.

speedybenz

SMG,

Great lap time. Now you need to break that 1.30 min mark!!. I would really like to come down and see how my C43 would do out there.

Maybe I can get all my parts on and get down to Willow Springs. I would really like to see how fast I could get around Turn 2 and the Turn 8 and 9 combo.


With all you tuning I doubt I could even come close to the time you are running, even with the hundreds of laps I have around their on my motorcycle.

Again, congrat's on the great laps.

Jeff

CynCarvin32

That could be but honestly Zepp its one of the wost tires I have ever driven on. I think conti sportcontact2's are worlds better!

I have to think that the C&D tire test was wrong ranking the T1-R that low. I know grassroots motorsport ranked the Falkin well but I dont see why. 2-3 laps and its a terrible greasy mess. Steve did a few 1:43's on those bad tires and the car was a tail happy wreck!

CynCarvin32

Hey speedy,

We have always wanted to see your car and how it would run so come on out! I have a feeling you are a bit quicker than a 1:35 given all the upgades and custom work you have done to that C43. The C32 still needs some different upgrades including a real suspension kit. The P-SS9 is nice but it really needs stiffer springs and far better shocks. Something along the lines of what you have would make the car at least 2-3 seconds quicker I think. Right now the shocks dont feel all that well matched to the springs but its the best kit offered for the W203.

smgC32

Hey Carl. Our hot temps are between 172 and 198. Although these were taken after we get into the paddock area so the temps will be higher. We are going to do some hot lap temps immediately off of turn nine to see where we are exactly. Given the fact that the camber cannot be changed easily at the track, we are somewhat limited in fine tuning the car and rely mostly on air pressures as our guage and seat of the pants feedback.

Tim. The T1-S felt much better than the 615's and you remember we went through about 10 sets of those. The T1-R should be similar to the S. I personally think that any street tire is fine for track work if you don't overdrive the tire. Running a 1:50 plus time at WSIR is possible with any tire on this car and if this time is the limit of its driver, the driver will be happy with that tire. When driving at the car's limit, the tire becomes much more important of a factor. The 615's just can't keep up with the car or our driving anymore. Also we must remember that the C32 is so heavy, so other lighter cars may have a better experience than us.

SpeedyBenz, it would be great to drive together at WSIR. I would be interested in comparing the cars and swapping rides. 90 is about as fast as we can go around turn two without the car washing out and causing excessive front left tire wear. A little slower saves significant rubber and longevity. Although we had some uneven wear on this day, many other cars were having much worse tire wear even with R compounds on some impressive track set up cars. We enter turn eight at about 125 and at this speed things get very unsteady for the sloppy rear end of the W203 chassis. We have tried faster but find that we come very close to the left edge of the track as the car drifts out and squirms about prior to the brake zone into nine. Turn nine also seems to be limited to about 90. If we gutted the interior and lost over 500lbs, as well as putting on camber plates, custom double adjustables and race springs, we just might break 1:30's, but that is unfortunately only a dream for us. Although a thought...

dorikin_86

I'm excited to see the AMG being pushed on the track

I also have Nitto nt01's on my s2000. Great tire for the money!

AWDman

you have no idea how PO'ed i am......to read this thread yesterday am, then step outside to shovel 6 inches of sleet and ice. arrgggh!

smg- thanks for the info it's highly apprecited. I take it the sizes you are running for nt01s are 18in? nitto's site does not show a 275/35-17.

also...just curious...for a standard radius corner (not decreasing) do you employ trail braking?

CynCarvin32

The W203 cars have what is called Electronic Brake Force Distribution. This feature is there to prevent the car from becoming light or tail happy when the driver brakes and corners at the same time. So with that system, the car behaves very oddly when you try to employ trail braking into a corner. You can do it and it does help make the car bite and "turn in" but only up to a point.

The system works by limiting the braking power given to the front and rear axle when the vehicle is turned. Whe this system takes effect, it feels like the car has terrible brake fade but in reality the computer brain is just limiting the force applied to the brakes.

The car seems to be more open to trail braking that it does having the brakes applied while the car is turning slightly. At Big Willow, tunrs 8 and 9 are a seemingly connected corner with a braking zone for 9 as the road tightens.

In this complex, the car requires that you be 100% straight on the wheel before you brake or it does not really want to slow down. You sometimes are turned just a tad bit and trying to scrub off a few mph's and the when that happens the car feels fairly unstable and "odd" just because the brakes dont engage as you the driver expect.

Coming into a corner straight on and "trail braking" into the corner does work a lot better but you can still feel the EBD system at work. Without using "trail braking" the car is sometimes very difficult to set up for a corner so yes it does help. You just need to learn how the EBD system works, when it engages and what it feels like when activated.

Fifth Ring

SMG, great job and write up. What kind of brake setup are you running?

I think the Grassroots Motorsports write up on the 615 was biased toward autocross use. Autocross is like track use EXCEPT for the sustained heat that track use creates. So it's not surprising that the 615 gets greasy when hot.

The NT-01 is an R compound, isn't it?

CynCarvin32

The car has a 4 wheel stoptech kit with pagid black pads up front and pagid orange pads in the rear. They held up well last week but this track is very mellow on brakes for the most part.

NT-01 is a R-comp tire and it is recommended for track use. The tire is very loud between 45-60 once scrubbed and would likely drive you INSANE on a daily basis. Its ride however is 100% smoother than that of the 615.

Making those tires fit the C32 was a real struggle. I wish I had video footage of SMG and my self doing whatever it took to make the tires fit. It would have made you either cry or laugh. It was all worth it and we caused no damage to the car. We really should open a tuning shop!

smgC32

Here are some pics of the tires and the new front black calipers, as well as the wheel stud kit.

The tires have held up better than any we have run so far. We have 15 sessions on both the front and rear. The fronts are about 75% worn and the rears only about 35%, so we could get another few sessions on the front, but at least 10+ more on the rears. I predict two sets of fronts for every one set of rears. The Nittos are better thant the Dunlop SPSSR's we ran for so long. The Toyo RA-1's shaved should be quite similar as they use basically the same compound. The Falkins just can tolerate the extended heat we put into the tire during back to back 30 minute sessions.

We are running Pagid RS-14 Black racing pads. We wear down the pad depending on the track about 3mm every track day. I am down to 4mm, or about the thickness of the backing plate after 15 sessions, or 7.5 hours of track time. This is the bare minimum and they won't last another track day. At about 230 a set of fronts, pads cost about 75 per day to run. The rears last much longer, around 40 sessions. The C32 is so front heavy that even the Pagid Orange, which is a great all purpose track/street pad, won't hold up well to repeat use at the track. Fade sets in much earlier with the Orange than the Black on the front. The Blacks have a higher maximum operating temperature.

The new black calipers disappear through the wheel more than the silver and the wheel studs sure do make changing the wheels easier.

Moviela

Congrats on hitting 1:35, you have dialed in the track pretty well. Very respectable times for a 203. You made the perfect choice of rotors that are slotted, but not drilled. I prefer bolts over studs, because I can toss them when changing tires, but you are right that studs are easier to "find." I stick a smooth pin in the rotor, and find that when approaching with the wheel, like threading a needle. Because the wheels are "hub-centric" a little wiggle is needed to seat the wheel. You might consider some Yoko's. I've been running them on my Porsche, they have eliminated the rice aroma and made a damn nice tire.

StealthAuto

VERY nice work!!!

AWDman

Thanks. i do try this into big bend at lime rock. works to differing degrees but i'm simply too inconsistent. wish i could get a few 1 hr sessions to sort myself out. the rule of thumb at lime rock is "S#it happens" ...and your session gets cut short.

smg i guess you are running 18s? and that why there were a pain to fit? too tall? i need too decide soon on my tires for this season. flim flamming between 235/35 hoosier R6 & 265/30 MPSCs on 19" or 245/40 hankook z214s on 17".

so who will be the first to run the track in dyno mode? given enough rubber and a LSD this may not such a daunting proposition.

smgC32

Tires are 18's only because we needed them to run the 355 stoptechs. I prefer 17's and there are many more size choices and brands in 17's. The height of the tire is not the issue. The 275 35 18's are 25.6" in diameter while the 265 35 18's are 25.3". A little over a quarter inch is within acceptable limits and will not make a difference. It is the huge width that was the problem in the rear. The side wall construction, rounded edge and buldge on the Nitto's are significantly "wider" than other tires. Even the fronts are wider when mounted. Unless you are willing to do some creative artistic molding of the fender wells, don't even try this. I think you will be better off with the 245's on all four corners with 17's. Less unsprung weight and reduced understeer by the narrower rear tire.