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Any autocross guys running MPSS (or used to?). Curious about street pressures

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Any autocross guys running MPSS (or used to?). Curious about street pressures

 
Old 05-09-2019, 07:57 PM
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K.I.T.T.
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Default Any autocross guys running MPSS (or used to?). Curious about street pressures

Trying to find an optimal cold pressure/hot pressure that seems to keep the tire livable but also readily available. Autocross guys have a very short stint, versus pouring heat into a tire via HPDE, so I figure an autocross pressure setup would be more in line with a street setup would be. I'm running 27psi cold, but the car feels pretty loose. I have no tpms on board, so figuring I am going to bump to 30 cold.

Anyone with any MPSS experience would be appreciated, this is first time I owned the tire, and currently wont be running any track days, just street time.
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Old 05-10-2019, 01:31 AM
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I started autocrossing with those tires. They never got any heat in them and sucked for autocross. I bought another set of wheels and put some Rival S tires on which are great. I used the MPSS until they corded on the street. Good for canyon and mountain runs but not cold autocross laps.
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Old 05-10-2019, 01:37 AM
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Originally Posted by K.I.T.T. View Post
Trying to find an optimal cold pressure/hot pressure that seems to keep the tire livable but also readily available. Autocross guys have a very short stint, versus pouring heat into a tire via HPDE, so I figure an autocross pressure setup would be more in line with a street setup would be. I'm running 27psi cold, but the car feels pretty loose. I have no tpms on board, so figuring I am going to bump to 30 cold.

Anyone with any MPSS experience would be appreciated, this is first time I owned the tire, and currently wont be running any track days, just street time.
28 rear, 30 front cold. 345/285. A couple seconds slower than equal drivers with 200 tw tires.


DH
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Old 05-10-2019, 05:45 PM
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I like the wet performance of the MPSS's, but being out in Vegas now, I don't think I have to prioritize that as much as I did in Ga. Some very high surface temps here though, so I also don't want to get into crazy wear rates. Overall, I've been very impressed with the MPSS...it's wear has been manageable, it's wet performance is suprising and WHEN they get heat in them, they're pretty serious tires but...seems that if I do a quick rip, the car is pretty loose and I'm thinking I'm just undershooting starting at 27psi cold because they aren't getting there with highway driving, even with pretty toasty surface temps.

Going to try 30 and see what happens.

Been doing a bit to adapt to the surfaces out here. I suspected Vegas would be pretty smooth, but frankly Ga is overall a lower frequency surface. The heat in Vegas seems to really give the roads texture, and they used a lot more concrete so you get a lot of undulations. I had to go a wee softer on my dampers to restore some ride quality and grip. Going to do another setup to drive around soon, just tryin to chip away at it.
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Old 05-13-2019, 07:45 PM
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If you can get your hands on 4S in the right size, they are quite a bit better than the MPSS and cost the same. Phenom in the rain and pretty good in the dry. I shoot for 36-37psi hot. Any more and they grease on a road course. On the street I keep them around 33 cold. They don't like to be cold though. You will gain nothing running them at low psi. I've run them on the Z and the V. They don't grip low psi and/or cold.
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Old 05-13-2019, 08:08 PM
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I intend to go 4s next, but I have some good life left in these MPSS's still, and the shoulders are holding up (I run aggressive street camber). I kept the pressure slightly low, to aid keeping the shoulders cooler as well. I'd like dial back a tad, but I need to get rollin on my carbon widebody for that stage. Right now my fitment is dead on at the current camber. I can straighten up a bit to mid 1's versus high 2's once I get goin there.
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Old 05-14-2019, 03:37 PM
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For every day use, 30 seems to work well. For track use, and left hand turns, I start at 27 at 3 corners, 26 for the right front. After my first session, I will adjust them all down to 30. I've tried the higher pressures and grip just goes away and that was the first heat cycle.
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Old 05-15-2019, 12:17 AM
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I have ran fronts at 32 and rear 30. The are faster 30 front 28 rear auto crossing. Sun on the course and higher ambient temps help. I havenít tried RE71Rs. But A7 Hoosiers are way better.
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Old 05-15-2019, 01:07 AM
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I was going an hpde I'm the morning and I was 32 cold on stock c6z wheels

once I ran a few warm up laps the next few at 8/10ths and tmps freaked saying I was at 40psi in all four....

pulled off and reduced to 35 hot and I felt much better handling.... (used manual pressure gauge)

I think was close to 28 cold the next morning, living in sfl....

went back to 32 for my daily driving and land about 35 psi warmed up driving off track.

drew

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Old 05-15-2019, 02:14 AM
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Raced a turbo'd VW tonight...oh boy...she's lively passin through 70...lol...need more grip...*** end all over the place.
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