Bob M

Hey Tim,
I keep them out of the sun, but the garage is not heated. With the kind of winter (several days below zero) we had last year and one that seemed to last forever (snow in April), I'd almost say they had been cryo'd! While that is a 'normal' storage temp for MI, maybe it didn't sit too well with the tires. That's the reason for my question. Actually, this brings up a thought, I wonder what would happen if you ran a set of tires, where they had "gone away" related to one too many heat cycles in them, through a cryogenic process? Would that bring the ,olecular structure of the tire back in the direction of new?
Regarding hot temps for the MPSC's, is there a point where the tires can be over temp'd? Given what seems to be my lower temps, maybe a moot point in my case.

Bob

ColorChange

Bob: Rubber is real weird stuff. I don't know it as well as I should but I would be surprised if freezing temps would have any affect. I do not think cryo'ing will help at all because I don't believe the molecular structure of the rubber would change, unlike many metals that might undergo a crystaline structural change. Since rubbers are so amorphous, this is unlikely, but again, rubber is extremely weird stuff so I can't comment with confidence.

George A

Ok, listen to my Cups in the video below. It was a little cooler than normal, so that might have something to do with it but then again my first set sounded the same.

MSR CR - Finish

George

993RSCS

The cups don't squeal at all in my car, which is interesting since it is also a 993 with same tire sizes. Perhaps it is the camber and spring rates, as I think I am running more camber than you are and certainly higher spring rates. Looking forward to racing with you again at Hallett.

Paul

DJF1

Thanks George. Watching your video its clear to me what I need to do... You dont have as much understeer at entry as I do, plus from what I can see you favor early apexes on some turns and keep the car on partial throttle. I clearly need to get rid of the amount of understeer I have, at TWS for example I get wheel skipping at the carousel when I push it and at the esses my front washes out by a car length at least if I try to do any kind of speed in there...
Thanks again!

George A

Paul, have you ran the car since the race? I know you didn't get enought time on the Cups in the car that weekend. Also, what hot pressures were you running? You know, even with only 2.5 degrees of camber I get even wear. Maybe the outer block is the one making all the noise. Finally, you know there is a BMW CR on the first weekend of August at MSR and they let pcars in. I'm doing it. BTW, for those interested, that's Paul's gorgeous white car behind me in my avatar.

Danny, wow you can get your front wheels to skip! That sounds like the stock 911's I've driven lately. You do have some serious understeer, but I think the carousel does that to most cars. You must also lose soooo much time through the esses which then carries onto the straight. Wow again. I don't know what makes my car different than most but I've never seen another 993 with as much oversteer as mine. I can't tell you how many times I've looped it as I tried to learn to drive it. If you didn't have your foot at least three quarters down on the gas, the back end came out. I learned to drive a really loose car but now I finally got it to where it has a little (just a little) understeer. The MPSC help, that's why I like them.

George

993RSCS

George,

I haven't driven it yet as the master cylinder hasn't been replaced yet. It is headed of to Denver for a checkup (Premier Motorsports) and then off to Brainerd for the PCA Club race the same weekend as the BMW race. Wally is going up with us, as are several others from Oklahoma.

I have 3 track days on the cups in my car, so certainly not enough data to make a good judgement, although even my pig 996TT didn't make the cups sing all that much.

Paul

993RSCS

Danny,

You might want to talk to Chris Cervelli about alignment/suspension setup of your 993. He set my car up and I have very neutral handling with the ability to understeer or oversteer based on right foot setting. Quite a change from my 996tt that plowed through the carousel.

Paul

993RSCS

George,

I have also been in the lower pressure group with my 993 (wt 2800lb) with 36 rear/34 front hot pressures. I haven't had a chance to check pyrometer reading yet although wear seems to be pretty even.

Paul

Dennis K

From your video, it looked like whenever you had terminal understeer or had to correct oversteer, the tires would sing. Same deal in my car. Whenever the slip angle was great enough, during big understeer or hanging the rear out, the Cups would squawk. I thought it was normal. My car weighs 3400 lb w/ me & fuel and I ran the Cups 36f/34r psi hot.

Here's a lap of mine on Cups. (25 MB)

DJF1

wow Paul... THAT would be a dream! I clearly have a LOT of work to do and use my suspension to its fullest abilty... It is VERY clear now that I do not use the tires to their fullest ability due to my suspension settings. Thanks for the confirmation that it can actually be done! This MPSC thread has actually been very helpfull!
Thanks again guys!

DrJupeman

My MPSCs squeal at the limit.

ColorChange

Mine squeal too. Not like a banshee like the PS2's, but they do talk.

George A

I'm glad mine aren't the only ones that squeal. I thought I got a bad batch.

Color, check out the black car that passes (laps) me toward the end of the video. That car started out as a 996TT, much like yours. He got it last year and started upgrading it almost right away, (Motons, cage, etc.). It's now a 3000 lbs / 500-700 hp monster that he races in the SpeedTV series. Yes, he outran all the cupcars and he has only been driving on the track for a year (which is amazing in itself).

George

38D

Mine squeal like a stuck pig.