Sport Cups tire pressures?
#1
Racer
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Sport Cups tire pressures?
Can any of you guys running MPSCs on C6 Z06 recommend starting cold pressures and target hot pressures for optimal grip and tire wear?
The Michelin brochure says 25/28 (F/R) cold, and 32/36 hot. However, I note that some guys prefer a couple PSI lower in the rears. Myself, I have found best performance on GY and Bridgestone runflats when the fronts are slightly higher pressure when hot, than the rears.
My camber settings are -1.2 front and rear. Track is Mosport.
Thanks in advance.
The Michelin brochure says 25/28 (F/R) cold, and 32/36 hot. However, I note that some guys prefer a couple PSI lower in the rears. Myself, I have found best performance on GY and Bridgestone runflats when the fronts are slightly higher pressure when hot, than the rears.
My camber settings are -1.2 front and rear. Track is Mosport.
Thanks in advance.
#2
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Also, I did not have Tire Rack heat cycle the MPSCs. Is this going to have a major effect on wear and, if so, is there anything I can do about it before heading to the track?
#3
Melting Slicks
The MPSC's go away real fast above 35-36 hot. So I like to run 34 hot max. I run F and R at the same pressure (hot).
I think most people agree that the TR heat cycling does nothing.
I think most people agree that the TR heat cycling does nothing.
#4
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Thanks, Dreamin. What would you guess as a good starting cold pressure to arrive at 34 hot? Maybe 26 or 27 psi?
#5
I agree, Keep them under 34 hot. Starting at 28 maybe...
You should use a LOT more front neg camber: these tires LOVE it. The rear could be more as well, but probably not too much more for Mosport. I'm currently running around -2.7f and -2.0r.
You should get a good probe pyrometer, and check the tire temps after sessions to find the best pressure settings.
At VIR I kept lowering the front pressures to keep the HOT pressure the same or lower than the rears and the temps even.
I love these tires
You should use a LOT more front neg camber: these tires LOVE it. The rear could be more as well, but probably not too much more for Mosport. I'm currently running around -2.7f and -2.0r.
You should get a good probe pyrometer, and check the tire temps after sessions to find the best pressure settings.
At VIR I kept lowering the front pressures to keep the HOT pressure the same or lower than the rears and the temps even.
I love these tires
#8
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Why would you want the rears to start lower? My fronts heat up more so if you are looking for equal pressure (34 or so) hot, wouldn't you start lower in front? I have been playing with it and found 25 front 28 rear to be closer to 34 hot all around.
I'm asking for advice rather than preaching that my way is right...
I'm asking for advice rather than preaching that my way is right...
#9
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I agree, Keep them under 34 hot. Starting at 28 maybe...
You should use a LOT more front neg camber: these tires LOVE it. The rear could be more as well, but probably not too much more for Mosport. I'm currently running around -2.7f and -2.0r.
You should get a good probe pyrometer, and check the tire temps after sessions to find the best pressure settings.
At VIR I kept lowering the front pressures to keep the HOT pressure the same or lower than the rears and the temps even.
I love these tires
You should use a LOT more front neg camber: these tires LOVE it. The rear could be more as well, but probably not too much more for Mosport. I'm currently running around -2.7f and -2.0r.
You should get a good probe pyrometer, and check the tire temps after sessions to find the best pressure settings.
At VIR I kept lowering the front pressures to keep the HOT pressure the same or lower than the rears and the temps even.
I love these tires
#10
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Why would you want the rears to start lower? My fronts heat up more so if you are looking for equal pressure (34 or so) hot, wouldn't you start lower in front? I have been playing with it and found 25 front 28 rear to be closer to 34 hot all around.
I'm asking for advice rather than preaching that my way is right...
I'm asking for advice rather than preaching that my way is right...
#11
Team Owner
Why would you want the rears to start lower? My fronts heat up more so if you are looking for equal pressure (34 or so) hot, wouldn't you start lower in front? I have been playing with it and found 25 front 28 rear to be closer to 34 hot all around.
I'm asking for advice rather than preaching that my way is right...
I'm asking for advice rather than preaching that my way is right...
Lots of guys who are very hardcore will have different pressures for right/left and front/rear depending on the track they run.
I find that I need to keep the rear pressure lower as I am much more likely to loose traction from rear coming out/around than anything else. So I want the front to come up to 34 max and the rear to stay lower.
Again .... this is my thinking and not to be taken as gospel
DH
#12
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Thanks for all the tips, guys.
I started them off at ~28 psi cold. It was a chilly day and Mosport is especially slick in the morning, when the track is cool. To be honest, took me a couple of sessions to feel 'em out and get any heat in them. Even so, I think I maxed out at 32 psi after lunch. I didn't have a chance to pick up a pyrometer, but judging by the level of grip and consistency I found, I believe I must have been close to the optimal temp range. I easily beat my best laptime on runflats by over a second.
Very impressed with the tires. Again, thanks for all the input.
I started them off at ~28 psi cold. It was a chilly day and Mosport is especially slick in the morning, when the track is cool. To be honest, took me a couple of sessions to feel 'em out and get any heat in them. Even so, I think I maxed out at 32 psi after lunch. I didn't have a chance to pick up a pyrometer, but judging by the level of grip and consistency I found, I believe I must have been close to the optimal temp range. I easily beat my best laptime on runflats by over a second.
Very impressed with the tires. Again, thanks for all the input.
#13
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I'm no expert but your premise may be wrong.
Lots of guys who are very hardcore will have different pressures for right/left and front/rear depending on the track they run.
I find that I need to keep the rear pressure lower as I am much more likely to loose traction from rear coming out/around than anything else. So I want the front to come up to 34 max and the rear to stay lower.
Again .... this is my thinking and not to be taken as gospel
DH
Lots of guys who are very hardcore will have different pressures for right/left and front/rear depending on the track they run.
I find that I need to keep the rear pressure lower as I am much more likely to loose traction from rear coming out/around than anything else. So I want the front to come up to 34 max and the rear to stay lower.
Again .... this is my thinking and not to be taken as gospel
DH
#14
With a lot of neg camber in the rear, there's quite a bit of 'transitioning' in moderate cornering(0.7-0.9G). It's really too much neg camber for the street and I will reset to around -1.5 when I switch back to the Generals for the winter. They don't have the rounded tread edges like the MPSCs.
#15
Why would you want the rears to start lower? My fronts heat up more so if you are looking for equal pressure (34 or so) hot, wouldn't you start lower in front? I have been playing with it and found 25 front 28 rear to be closer to 34 hot all around.
I'm asking for advice rather than preaching that my way is right...
I'm asking for advice rather than preaching that my way is right...
Knowing what change makes the difference you want in the car's performance is one of the really challenging aspects of racing... I mean HPDE...
Being able to tell if you made the RIGHT difference is much harder though. Often, the most comfortable setup is not the fastest.
#16
Racer
Interesting
I always ran mine at 36 Hot, 29 front/30 rear cold. The brakes/engine heated up the fronts
I have never tried to go lower as Michelin produce a guide book (although aimed at Porsches) that maintains 36 is the correct figure
I will reduce by 2psi and aim for 34 Hot and report back next week
John
ps. I use 265 x 35 x 18F and 325 x 30 x 19 rear as that is all that is available to me locally.
I always ran mine at 36 Hot, 29 front/30 rear cold. The brakes/engine heated up the fronts
I have never tried to go lower as Michelin produce a guide book (although aimed at Porsches) that maintains 36 is the correct figure
I will reduce by 2psi and aim for 34 Hot and report back next week
John
ps. I use 265 x 35 x 18F and 325 x 30 x 19 rear as that is all that is available to me locally.
#17
On camber - I was running -1.5 in the front and noticed that the outside edges were wearing badly. I bumped it up to -2.5 but the outside edges were still corded after two more track days while the rest of the front was in pretty good shape. I'll be interested to see how long your fronts hold up at -1.2.
FWIW the rears are still in great shape but I'm moving to Hoosiers now.
FWIW the rears are still in great shape but I'm moving to Hoosiers now.
#19
Team Owner
Interesting
I always ran mine at 36 Hot, 29 front/30 rear cold. The brakes/engine heated up the fronts
I have never tried to go lower as Michelin produce a guide book (although aimed at Porsches) that maintains 36 is the correct figure
I will reduce by 2psi and aim for 34 Hot and report back next week
John
ps. I use 265 x 35 x 18F and 325 x 30 x 19 rear as that is all that is available to me locally.
I always ran mine at 36 Hot, 29 front/30 rear cold. The brakes/engine heated up the fronts
I have never tried to go lower as Michelin produce a guide book (although aimed at Porsches) that maintains 36 is the correct figure
I will reduce by 2psi and aim for 34 Hot and report back next week
John
ps. I use 265 x 35 x 18F and 325 x 30 x 19 rear as that is all that is available to me locally.
I have the 285x30x18 fronts....