09-09-2018, 06:01 AM | #1 |
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Chunked: MPS4S
At a track weekend this September, a less than two month old MPS4S tire chunked. One chunk actually revealed a chord so I guess the life of this tire has come to a very short and unhappy end. I was running 38PSI hot on the tire that died. PSI seemed reasonable but there was no doubt the tire was rolling over itself. I guess a hot temp of 40-42 might have been a better choice despite the greasiness I feel as they warm up after a few laps.
Any suggestions on how to prevent 'chunking' in the future at a track day with these tires?? Thanks. |
09-09-2018, 06:54 AM | #2 |
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On which kind of turns was the tire rolling over itself like in an auto-X ? If it was a rather slow very tight bend under hard braking - then sometimes driving style changes ( minus suspension changes ) and of course tire inflation.
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09-09-2018, 11:35 AM | #3 | |
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How did you determine that you were running 38 psi hot? There are quite a few photos across the 'net showing chunked, corded, and otherwise used-up MPSS' after a single track event. The 4S is susceptible to the same issues. Lack of negative camber, too-high or too-low tire pressures, over-driving the car into the corners, and street braking will all contribute to heating the tire to a point where it gives up. I've come to the conclusion that street tires in this category aren't suitable on race tracks when placed on relatively heavy, high-horsepower cars.
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09-09-2018, 12:23 PM | #4 | |
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Changing your driving style would help, do very late apexes and sharp turns at lower speed instead of plowing into corners But the real answer is to use a different tire |
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09-09-2018, 01:22 PM | #5 |
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Extreme performance tires will hold way better for track use.
Or drive at little slower pace at the track. MP4S can be rolled over badly. I auto crossed with MPSS and I had to pump up to 48psi hot in front. Now with RE71r, I can stay at 32psi hot. (or even lower) |
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10-07-2018, 08:33 AM | #6 | |
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10-09-2018, 02:41 PM | #7 |
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get a tire made for the track.
re71r's, nt01s, direzzas, etc...
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10-15-2018, 07:24 PM | #8 |
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MPS4S are wonderful tires for the street, great grip in the wet and super smooth and quiet. Love em and enjoy the n the street. Get a 17 inch square set up and 225/45/17 Potenza RE71 for the track. They are noisy pick up debris sand like a wheel bearing is going out and sick like glue. MPS4S will help you to enjoy the RE71s and visa versa. you'll need a harbor freight 1.5 ton jack and torque wrench too ..
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