Going to try race tires (R888); any pointers?
02-21-2008, 04:24 PM
#46
Rennlist Member
I assure you, shaved RA1's are no 1-2 heat cycle tire. I bought mine used, with 1-2 heat cycles on them, from WC teams. I could get approximately 2 full weekends of 4 to 5 H-A-R-D sessions per day (usually with passenger) out of them, depending on the track. And they got better & better up to the very point they corded.
02-21-2008, 04:31 PM
#47
Race Director
I agree.
4/32nd shaved RA-1 last a long time. However as used in World Challenge their goal was outright speed and never tire life.
Here are some quotes from a 944 spec racer who ran in World Challenge for bit.
Of course he also thinks we will run shaved tires in the future. I am not so sure that it will be the thing to do in 944 spec however since our cars are much softer sprung that WC cars.
4/32nd shaved RA-1 last a long time. However as used in World Challenge their goal was outright speed and never tire life.
Here are some quotes from a 944 spec racer who ran in World Challenge for bit.
As a former participant in the Speed World Challenge, I can tell you that the RA-1s are supposed to be shaved to 3/32s for all competitors. Now, that's not to say that some teams don't re-shave them, but I've never heard of anyone doing that and all other tire aids are illegal. It was commonly understood that a set of new tires had 1-3 fast laps in them for qualifying and then they would drop off a little. Tires were then required to be used for the race. The top teams would litterally toss them after the race regardless of their condition. And, I've dumpster dived for more then a few sets of their tackoffs. At $205/each for a new tire and $25-40/each for a used one, it was a big money saver for practice tires and even some raceable ones.
However, my practice was to run a set of new tires up front (FWD touring car) for qualifying and race, then move them to the rears for the next qualifying/race. I would then use the post-race rear set for practice sessions and in general I could get anywhere from 5-15 additional heat cycles out of them before they would cord. A set of unshaved tires would maybe last 5 heat cycles total before chunking or cording.
With the R888 being the same basic compound with a different mold and construction, I expect the teams to treat the tires no differently. While the characteristics of the tire might be a little different and some cars will have to modify their setup, I would expect all cars to be on shaved tires at Sebring next month. Unshaved tires will only be used for rains. Just a guess, but a well informed one.
Rick
_________________
Rick Snyder
However, my practice was to run a set of new tires up front (FWD touring car) for qualifying and race, then move them to the rears for the next qualifying/race. I would then use the post-race rear set for practice sessions and in general I could get anywhere from 5-15 additional heat cycles out of them before they would cord. A set of unshaved tires would maybe last 5 heat cycles total before chunking or cording.
With the R888 being the same basic compound with a different mold and construction, I expect the teams to treat the tires no differently. While the characteristics of the tire might be a little different and some cars will have to modify their setup, I would expect all cars to be on shaved tires at Sebring next month. Unshaved tires will only be used for rains. Just a guess, but a well informed one.
Rick
_________________
Rick Snyder
Of course he also thinks we will run shaved tires in the future. I am not so sure that it will be the thing to do in 944 spec however since our cars are much softer sprung that WC cars.
Last edited by M758; 02-21-2008 at 04:47 PM.
02-21-2008, 05:31 PM
#48
Rennlist Member
My RA-1s would HC out at about 27.....3 sets in a row did that. Probably not too far off from cording, but I didn't see any. Drop off of grip at HC 28 was very noticeable. Up to that point I thought they were consistent. Better than my Hoosiers at 15 HCs....still working on the BFGs.
02-21-2008, 09:17 PM
#49
Three Wheelin'
I can give you some suggestedd starting pressures for TWS and MSR and ECR that have worked for me
Let's talk about this @ ECR in a couple of weeks. I've been running Michelin slicks for so long on the Cup, I'm going to have to start from scratch on the DOT stuff again. Back when I did run them on the RSA, I ran Hoosiers & MPSCs so I have "0" experience with Toyos.
PS: I have a new steed you may want to "test drive".
02-21-2008, 09:32 PM
#50
Rennlist Member
Dave,
Let's talk about this @ ECR in a couple of weeks. I've been running Michelin slicks for so long on the Cup, I'm going to have to start from scratch on the DOT stuff again. Back when I did run them on the RSA, I ran Hoosiers & MPSCs so I have "0" experience with Toyos.
PS: I have a new steed you may want to "test drive".
Let's talk about this @ ECR in a couple of weeks. I've been running Michelin slicks for so long on the Cup, I'm going to have to start from scratch on the DOT stuff again. Back when I did run them on the RSA, I ran Hoosiers & MPSCs so I have "0" experience with Toyos.
PS: I have a new steed you may want to "test drive".
Why are you going to DOT rubber, anyway?
My curiosity as to whatever it is you have acquired is now at full boil....
02-21-2008, 09:34 PM
#51
Three Wheelin'
.....not a 911.
Check the sig. line & avatar, Einstein
PS: I would think you would start lower in the front since you have added weight there to load the tires. On the cups, we always started 2 lbs. higher up front because they would never grow as much as the rears. On hot days, we were at 21 front, 19 rear to end up @ 30 all the way around (using air not nitrogen).
02-21-2008, 09:45 PM
#52
Rennlist Member
Ah....a race Boxster....sweetness. Did you unload the Cup?
Yeah, you would think it would be the other way around, but running the fronts a little bit higher COLD gets rid of the last vestiges of understeer (if I have the suspension adjusted right, which I am still figuring out at ECR, given my shortened weekend last time), and looks perfect on the probe pyrometer. At TWS 2 weekends ago, until the RA1's finally corded in dramatic fashion, the car was probably the most balanced, perfect it has ever been there. I started fronts at 24, rears at 21. Go figure.
Yeah, you would think it would be the other way around, but running the fronts a little bit higher COLD gets rid of the last vestiges of understeer (if I have the suspension adjusted right, which I am still figuring out at ECR, given my shortened weekend last time), and looks perfect on the probe pyrometer. At TWS 2 weekends ago, until the RA1's finally corded in dramatic fashion, the car was probably the most balanced, perfect it has ever been there. I started fronts at 24, rears at 21. Go figure.
02-21-2008, 10:06 PM
#53
Three Wheelin'
Yeah, I'm lost on front engine stuff.
Yep, the cup is history. Amonds have it now. It was getting, shall we say, a bit exorbitant to operate. I'm a junkie & seat time was getting too pricey. Tires/fuel/support are up over 35% since I started 3 years ago. Since ECR is only 30 minutes away, I plan on spending quite a bit of time there. The cup just wasn't practical for that & nothing beats being able to jump in the Boxster to drive out there for some hot laps. Just to give you an example, I figure running the Boxster @ TWS next month will be about $ 3,500 less for the weekend then in the cup on tires, fuel & support alone. It was FUN while it lasted though. What a great car! I'm sure another one is in my future
Yep, the cup is history. Amonds have it now. It was getting, shall we say, a bit exorbitant to operate. I'm a junkie & seat time was getting too pricey. Tires/fuel/support are up over 35% since I started 3 years ago. Since ECR is only 30 minutes away, I plan on spending quite a bit of time there. The cup just wasn't practical for that & nothing beats being able to jump in the Boxster to drive out there for some hot laps. Just to give you an example, I figure running the Boxster @ TWS next month will be about $ 3,500 less for the weekend then in the cup on tires, fuel & support alone. It was FUN while it lasted though. What a great car! I'm sure another one is in my future
02-21-2008, 10:11 PM
#54
Rennlist Member
02-21-2008, 10:29 PM
#55
Three Wheelin'
Yeah, brotha. They ain't cheap to operate. This cupcar racin' be for them big sack boys Add in $ 700 or so for entries, transport @ a buck a mile (Road America is 2200 miles r/t, by the way), brakes, lodging, food, LOTS OF BOOZE, etc. & you can go 5 figures @ a big race pretty damn quick
PS: Remember, the $ 3500 is the DIFFERENCE in tires, fuel & support between the two cars not the total cup cost! I still plan on having some light support even with the BSR car. Makes you appreciate that little joy ride you had in mine, huh Spanky
Add in $ 700 or so for entries, transport @ a buck a mile (Road America is 2200 miles r/t, by the way), brakes, lodging, food, LOTS OF BOOZE, etc. & you can go 5 figures @ a big race pretty damn quickPS: Remember, the $ 3500 is the DIFFERENCE in tires, fuel & support between the two cars not the total cup cost! I still plan on having some light support even with the BSR car. Makes you appreciate that little joy ride you had in mine, huh Spanky
02-21-2008, 10:43 PM
#56
Rennlist Member
Yes, indeed. In retrospect, I wish I had pushed it just a wee bit!
02-22-2008, 01:00 AM
#59
Three Wheelin'
I think it's been more then a few months. Things really started ratcheting up within the last 6 months or so. The first couple of years weren't too bad.
02-22-2008, 07:50 AM
#60
Rennlist Member