As I had mentioned in another thread, I had a friend of mine co-drive my C32 at the recent MBCA/GWS DE at Summit Point. I had previously loaned my friend the C32 for normal driving, so this was the first time he got to drive the C32 on a road course. I also lent the car to him so he could do an autocross yesterday. He knows how to toggle ESP on and off, but doesn't know how to engage dyno mode.

When I loaned my C32 to my friend for normal driving, he told me that he didn't like the way the C32 brakes felt. Specifically, he didn't like the fact that it requires a lot of brake pedal pressure and travel to apply heavy braking. Apparently, on his current M3, it requires little pressure and movement to fully apply the brakes.

After Summit and autocross, he liked the brakes on the C32 even less. In my car, at least, if you're at, say 130 mph and you transition quick and hard (track style, not slamming on the brakes) and maintain heavy brake pressure, the back end of the car becomes unstable. Also, he felt that notwithstanding the magazine reviews of the C32 which puts it braking within a couple feet of the E46 M3 at 60, 70, and 80 mph, that the C32 brakes are very bad at higher speeds. For low speed hard braking, such as you might do on an autocross, I think he feels the heavy brake pressure and the relatively longer pedal travel required in the C32 hinders car control.

His background is from driving his current E46 M3 6-speed, a previous E46 M3 SMG, a E36 M3 with an AA tubro, and a E36 325i to M3 conversion, so he's driving quite a few more cars on the track than I have. My only other car on a road course was my E36 330i, which steered better than the C32 but was nowhere capable of reaching the speeds the C32 can on the straights.

For those of you who have significant track and/or autocross experience, especially also in cars other than the C32, what are your feelings about the C32 brakes, and overall handling?

As some may also know, I am currently awaiting the hardware components of my Evosport Stage-1 upgrade. For those of you who have done this or similar power upgrades, how do you think the brakes hold up against the increased power?

 

yuck yuck yuck...
thats all i have for the AMG brakes on the C32 It just won't stop our 3600lbs C32 although i never had brake fade...
Handling? I got beat by a stock llooking 96 Altima without any suspension mod with a real racer who raced for more than 30 years everyone on the track is really amazed by his pro driving... or i SUCK

 

The C32 will ociliate if your moving the steering and into the ABS at the same time regardless of speed. It is even worse in the short wheel base SLK32. Probably twice as bad.

Well I hope you used the brakes in the 330i. I think if you are comfortable with the current setup then it is fine, just foreign to your buddy. At Beaverun a few years ago at a MBCA function a friend of a friend showed up in his E46 M3 manual trans. We played tag following each others lines and in the end got three timed laps. During our practice it was interesting to see both cars accelerate at the same pace through 115 MPH. He was trying different gears and different lines to get more speed out of the last turn for the straight. But could not regain the 2-3 car he was looseing coming out of that turn. He was a little perturbed by that and at the timed runs where he was over one second behind mine. Since our acceleration was very similar I had to assume that braking task were similar. Guess who was taking it easy on his brakes during practice? He was already on his 3rd set of rotor because of cracking.

With your power increase I am more concerned about your tires. With DOT race tires the stock brakes are fine. The extra grip out of the corners leads to higher trap speeds and more stress to the braking system at the end of the straight.

Don't someone tell you you have a problem with your brakes because you'll convince yourself that you do. I think I have diagnosed this as a west coast syndrome. ;^)

Norm
Bordeau/Merlot

 

derAMG, we have a Nissan Sentra that will run rings around just about everyone at the autocross. It is amazing what corner speed the driver can carry for the little ~115hp four!

 

Believe it or not, I thought for the street, the C32 has some of the nicest brake feel around. I liked the progressive behavior and longer pedal travel which allowed better feel and modulation in application. I had an opportunity to drive the C32 several times during track set for one of our schools I instruct for at the Big track at Willow Springs prior to the BBK. After finishing set up we run a few laps to see if the markers are in the right place at speed. I mentioned in another thread or on C32life a while back that the car's rear end was extremely unstable under moderate braking from speeds of 130+ to 80mph. No engagement of ABS, 85% pressure, steering wheel perfectly straight with brake release prior to corner entry. I feel that the squirming you are experiencing is due to the multiple bushings in the rear made from a soft rubber compound. There is too much weight in the front of the C32, especially with the stock suspension and ride heights. Under heavy braking there is a great transfer of weight to the front and the rear gets light. RENNtech does make a rear subframe modification, but at a price most will pass on. Upgrade your pads first in the stock calipers and then re-evaluate.

 

Presently I'm runnning Axxis Deluxe front pads, stock rear pads, and StopTech stainless steel lines at all four corners. A few months ago I had ATE Type 200 fluid, but the even more recent Service B flushed it back to the OE fluid.

At Summit, I wasn't pushing the car, so I limited my travel down the main straight to only 110-115 mph. There was no brake fade from any of my sessions. My friend took the car to at least 130 mph, but he was uncomfortable with the brakes, so he braked longer than he normally would. He didn't report any fade either, but we noticed a rather large amount of the Axxis Deluxe pads were missing after each of his sessions. Further, when I would get into drive the 2nd next session, when I started up the car I noticed that the pedal would travel further down on the first depression than normal. But after they it appeared normal.

I had once considered getting a StopTech BBK, but realization that I wasn't pushing the car that hard stopped me. Additionally, it was somewhat unclear as to whether the 355mm StopTech front kit would fit over my 18x8 SSR GT3 front wheels on 3mm spacers.

smgC32, are you running the 355mm StopTech front kit or the smaller (332mm?) StopTech front kit? Are you also running the rear kit as well? Also, is the braking instability also present with the BBK as well?

Going with a new front pad is probably the most logical solution, as I should probably rebleed the brake fluid back to ATE Type 200 and the current front pads are pretty thin. What pads might be better than the Axxis Deluxe, keeping in mind that I rarely do track and like to be as squeek free as possible and that cold stopping power would be a good thing as well.

Incidentally, I think the C32 is a capable car, however, it doesn't inspire confidence. It seems to me if you are already a highly skilled driver, you shouldn't have much of an issue with the car, but if you still have a lot of learn, its an intimidating vehicle to learn in.

 

i think a better suspension will makes C32 more capable..
http://www3.sympatico.ca/kng000/s2kru.avi
here is a video i captured chasing the slowest S2000 on site...but still, it is equiped with race suspension setups.

 

I was impressed with the C32. I was the co-driver at the MBCA event. I am trying to get Chris to post video's of me following/chasing cars. An empty road is boring to watch!

Take my comments with a grain of salt since I don't own one. The C32 is a capable car in the hands of a decent driver; but, it's really not meant for track and DEFINITELY not for auto-x. That open diff just kills your ability to put down any meaningful power out of a corner. Problems I felt were: a) brakes -- not good enough at high speeds; b) steering input -- becomes progressively worse at higher speeds; c) body roll -- car transitions to much weight in the corners, to much in accelerating, and to much in braking, upsets the car; d) pushes -- chris has made it understeer even more w/225 in the front and 255 in the rear ... in the carousel, car liked to push ...; and e) car likes to downshift in corners....

That said, however, I lapped the C32 driver and I easily passed the E46 M3 driver. So, if you are a decent driver in the C32, I would say you could beat 90% of the E46 M3 driver's. You just have to adapt your style of driving to the C32's quirks.

What Chris is not showing you, I believe the only two cars that passed me were the WRX (also a C32 owner -- on r-comps) and the Saleen 281-type r. I held off the 03' porsche C4S (on r-comps) ... easily went by the E46 M3 ... passed the S2000 w/o to much difficulty, etc. So, for the most part, the C32 can hold it's own.

The E46 M3 is a great car; BUT, it allows a pathetic driver to be a semi-decent driver. Hence, why so many damn M3 owners crash their car. The C32 is not like that. To drive it fairly well, you have to be a fairly decent driver IMO. Not everyone could get in and drive the C32 semi-hard around a road course. Chris knows, I am not a big fan of a lot of high HP. Anyone can get in an mash the pedal in a straight-line. It takes a lot of skill to negotiate a 3600 lb car (basically, an elephant) around a road course with any skill.

The M3 is no lightweight either. With 3/4 tank of gas --- the car weighed 3485 lbs WITHOUT a driver. So, it's not that far off from a C32's weight. If you are ever curious about autocrossing, they put you in AS against the Z06's ... although, didn't do to bad ... was about 2.5 seconds off their times on a 56 sec FTD course and they were on hoosier's. But, in essence, it will never be competitive in auto-x ... to much weight, to little tire, and no LSD.

 

Can't agree more...
me and my friends M3 keep chasing each other... we can't pull away each other nor chase up close to each other. At the end, he flies off to the grass...

 

Correct NoSoup4U! I can run and have beat non-Z06 in autoX, but a Z06 with suspension adjustments(i.e. camber and lowered), 50mm bigger rubber, and 500 lbs. lighter physics play a dominating roll compared to the C32. Not to mention 50hp and 65 trq deficit.

The C32 is portly but handles it's weight well.

Norm

 

I cannot confirm you fitment with the SSR's, but they clear fine with the Monolites.

I have the StopTech 355's up front and the 328's in the rear, both ends utilizing the new GENII calipers.

I have not run the same track I had experienced the squirm on since the BBK upgrade, but with the RS suspension on full firm running at SOWS, the problem is not evident here, although the speeds are significantly lower.

If you are loosing pad material by chunking, you are probably exceeding the operating temperature of the pad. Try something else. How did the stock pads hold up? Try the Porterfield R4-S for a good street pad with limited track capabilities, or go for the R4-E's which a few have already run with good results. Maybe the others can comment on their track impressions with these pads as well as mentioning how much squeeking they do on the street.

 

That was me in my WRX. You catch a glimpse of me in the latest video cschow posted with the two C32's behind me. I'd love to see some video of me in the WRX from outside the car...e mail me if you can share. The Mustang your referring to (red one in the pics from cschow in the other thread?) is a Cobra R 351 totally tricked out and stiffened chassis...it's a race car. BTW...It was nice to meet you guys there.

I think I mentioned I've been autocrossing the C32 in the MB club series. I would be much faster in the WRX but the club wanted some more competition in the AMG class. You're definitely right about the open differential being a big problem on the autocross course. You really have to be careful with the throttle to not just spin up your times. It is a big challenge to autocross the car but I also beat some much better suited cars and suprising people with the C32 is always fun. Here's a link to some of 2004 results; you can compare them to some other makes/models:

http://www.gws-mbca.org/ax/ax04-1.html

I think autocross #2 & 3 are posted as well. #4 was in the rain so it was interesting, I focused on smooth inputs and did pretty well winning the AMG class of 5 cars.

I ran R4E's at Mid-Ohio in the C32. Very good bite/brake torque, good wear, no fade, no pad deposits to burn off after the event but extremely noisy on the street. I didn't use the brake "shims" that the OE pads have so maybe that was the problem. They are much more noisy than the Carbotech XP9 track pads I use on my WRX. Next time I'll try to use the shims with them but I won't use them on the street.

 

Hi Carl:

Nice to meet you too. I can look through the tapes again and see what I have of the WRX.

 

NoSoup4u,

Good observations. The brakes and the rear of the car are the scariest part at the end of the straight. It just requires confidence in knowing that the car isn't going to lose it and the brakes will continue to bite down. You can outbrake a lot of cars believe it or not with the stock braking system.

Now the squirm in the tail is very very disturbing especially when you first experience it. I had only mildly experienced it when I was in NHIS at the end of braking on the main straight coming into the chicane. That was from 110 or so down to 40 - 50 (not sure on the exact numbers). The car's rear feels like it will break loose but not that bad.

In summit point it felt almost 50% worse probably due to the speeds you can achieve. I also ran without spare which may be a mistake as that further shifts the weight bias forward. I think I may run a spare tire from now on and see what that does.

It does push a lot in the carousel and that is where I think you can pick up a lot of time in this car because you can go pretty fast in the other areas.

It feels very disconnected on the small kink right before the big brake for the chute but it will be. The steering gets progressively worse as the speed is higher.

The carlsson's help a whole lot though and it eliminates a lot of sway especially in the carousel.


smg,

The carlssons did little to help the squirm on the rear end. I ran with them both set to 5's and thought it isn't a fair comparison being different tracks I can definitely say the problem is still there. Will run on Sept 10th at the same track and see if it has improved.

Prasith

 

C32 brakes and high performance driving doesn't compute...LOL

it just doesn't work as good as the M's on the track, but on the road it's good enough to do some sprited driving.

 

Two years with stock brakes on the track with no problems.

Running Porterfield race pads and race fluids.

 

I changed from #3 spring pads to #1's with my RENNtech springs and the tail squirm under braking seemed to have been reduced quite a bit.

I think you'd need a car set up with track spec negative camber not to have some amount of understeer in the Carousel. A recent instructor I had at Summit described the Carousel as throw away turns. There is more to be lost there by overcooking it than there is to be gained by pushing it hard (no pun intended). Building good steady momentum with a smooth consistant arc to the apex seems to be the ticket.

 

Frank, if you are referring to the M3's brakes, they too fail at the track quite often when pushed to their limit. BMW replaces more rotors than MB due to "warping" or more likely pad deposits.

I agree with Carl, the lower the rear ride height, the more stable the car under heavy braking.

BMW Instructor, are you running the R4-R's or E's? Have you consistantly run the stock pads with stock fluid for multiple sessions at a heavy braking track to comment on their performance vs. the Porterfields?

 

I am running R4-R's

No, I have never run stock pads on the track.

I can only say that the R4-R's have worked great and with no complaints.

 

Most MBCA events the C32 had stock pads and fresh OE fluid.

I am using stock pads, ATE blue, and cryo treated rotors.

Norm

 

The friction coefficient of the R4-R and E pads are almost double that of the stock pads. In addition, they can withstand operating temperatures exceeding 1200 degrees F. I use to run the R4 race pad on my BMW for many years until they came out with the E compound. I have found that the E compound takes a little while longer to heat up, but maintains extended high temperatures better than the R4-R and last a little longer. If I was running one race only, I would use the R compound as they would be in their operating temperature quicker, but for an extended track day of over 4 hours of running, I prefer the E compound. You should give them a try next time. I think you will like them.