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Discussion Starter · #1 ·
After several track days my Michelin PS4 tires on my 2016 Cayman S have significant wear on their shoulders (no surprise), so much that they wouldn't pass a DE tech. The rest of the tire surface shows little wear. I am fully aware that these tires are designed with an "outside". But has anyone tried reverse mounting them, that is, so that the "inside" is on the outside of the wheel? If so, how well has it worked or not worked?
 

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You cant flip 180, I think the compound on the tire is actually diferent inside to outside, I did end up switching to the Hankook RS4, I flip them after 2-3 3 day track events
 

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Discussion Starter · #3 ·
You cant flip 180, I think the compound on the tire is actually diferent inside to outside, I did end up switching to the Hankook RS4, I flip them after 2-3 3 day track events
I have stock 19 inch wheels (8J and 9.5J I believe) and it appears that Hankook RS4 don't come in stock sizes (235/40 and 265/40). My suspension is essentially stock PASM. What size RS4 are you using?
 

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Can't do that on the Michelins. There is a reason they are marked "outside" because as stated, the compound and tread design is different on in the inner half of the tire vs the outer by design, and you may get a nasty surprise trying to run them backward.

There was a post a couple years ago regarding someone doing this on the track, and they said it was quite the challenge and unpredictable from my recollection
 
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Discussion Starter · #7 ·
Yep, the only safe solution is to increase camber for the 'next' set of tires for at least -2 to -2.5
Agree, my current alignment is stock, except I asked for maximum negative on the fronts (with all stock hardware) which ended up -1.5. Rears ended up -1.6.
 

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I have stock 19 inch wheels (8J and 9.5J I believe) and it appears that Hankook RS4 don't come in stock sizes (235/40 and 265/40). My suspension is essentially stock PASM. What size RS4 are you using?
I use 18 inch size, you could consider a 245/35/19 and 275/35/19, I would consult a tire specialist but that could be a option.
 

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I use 18 inch size, you could consider a 245/35/19 and 275/35/19, I would consult a tire specialist but that could be a option.
I have stock 19" wheels and I use this size tire combo on them without issue. I do have about -1.6 camber front and rear as well as PASM.

Speedo will read 3% faster as these tires are 3% smaller circumference than stock.
 

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Discussion Starter · #10 ·
I have stock 19" wheels and I use this size tire combo on them without issue. I do have about -1.6 camber front and rear as well as PASM.

Speedo will read 3% faster as these tires are 3% smaller circumference than stock.
I've given up on flipping the PS4s and have a set of Hankook RS4s on order 245/35-19 and 275/35-19. I'll be trying them out at Mosport in a couple of weeks. What tire pressures are you using?
 

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I've given up on flipping the PS4s and have a set of Hankook RS4s on order 245/35-19 and 275/35-19. I'll be trying them out at Mosport in a couple of weeks. What tire pressures are you using?
To be clear, while I have those tire sizes on my track tires, the tires themselves are Firestone Indy500.

I ran 29 front and 30 rear, cold, at Eagles Canyon about 6 weeks ago. It was 103 that day and pressures peaked at 41 hot.

I am not the fastest guy on the track.
 
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