Can I go this wide?

[Liongolfer]

I'm hoping to get your thoughts if I can run 285/30/18 for my rear Cayman 987.2S lowered with B8 and R springs. I'm on BBS SR rims and have 7mm spacers on the front and 15mm spacers on the rear. Currently running PSS 245/4018 for the fronts and can get on a new set of PS2 285/430/18s to replace my end of life PS2 265/40/18s.

Maybe its the covid supply chain issues and me not being on 19s but its really hard on my shores to get a good set of tires for now. Michelin still does not bring in the PS4S in 18s and they have stopped PSS here as well.

The new set of 285/30/18 PS2 are a NOS N spec set YOM 2018. Not ideal but perhaps will bide me time till supply chains recover and right fit tires are more readily available then.

With my spacers and lower stance and BBS SR rims which already have more offset, will the 285s be too aggressive and have rubbing and safety issues. I think I'm on rather neutral camber front and rear.  No tracking for me.

 

Current rear tread depth is slightly under 4mm and fronts are 7mm.

 

Thanks in advance. 

[Andrea]

1 hour ago, Liongolfer said:

I'm hoping to get your thoughts if I can run 285/30/18 for my rear Cayman 987.2S lowered with B8 and R springs. I'm on BBS SR rims and have 7mm spacers on the front and 15mm spacers on the rear. Currently running PSS 245/4018 for the fronts and can get on a new set of PS2 285/430/18s to replace my end of life PS2 265/40/18s.

Maybe its the covid supply chain issues and me not being on 19s but its really hard on my shores to get a good set of tires for now. Michelin still does not bring in the PS4S in 18s and they have stopped PSS here as well.

The new set of 285/30/18 PS2 are a NOS N spec set YOM 2018. Not ideal but perhaps will bide me time till supply chains recover and right fit tires are more readily available then.

With my spacers and lower stance and BBS SR rims which already have more offset, will the 285s be too aggressive and have rubbing and safety issues. I think I'm on rather neutral camber front and rear.  No tracking for me.

 

Current rear tread depth is slightly under 4mm and fronts are 7mm.

 

Thanks in advance. 

 

with the /30 I'd worry more about you overall diameter which is 6.5% smaller than stock.  That might mess up with the PSM. Also it will sit your car another 20mm lower at the rear. (not to mention you'll reduce the rake angle of the whole car.

 

285/35 is a much closer to stock and preferred.

 

Regarding width, there isn't just one answer fits all. This depends on how much negative camber you are currently running, rim offset and rim width.  If you post those specs then it's easier to work it out by using a simple online tool: https://www.willtheyfit.com/

 

Another thing to consider is your car will tend to understeer more if you only widen the rear and not the front. 

 

 

[Liongolfer]

2 hours ago, Andrea said:

 

with the /30 I'd worry more about you overall diameter which is 6.5% smaller than stock.  That might mess up with the PSM. Also it will sit your car another 20mm lower at the rear. (not to mention you'll reduce the rake angle of the whole car.

 

285/35 is a much closer to stock and preferred.

 

Regarding width, there isn't just one answer fits all. This depends on how much negative camber you are currently running, rim offset and rim width.  If you post those specs then it's easier to work it out by using a simple online tool: https://www.willtheyfit.com/

 

Another thing to consider is your car will tend to understeer more if you only widen the rear and not the front. 

 

 

 

Thanks for this.  Yes, I spoke to a tire guy and he expressed the same height concerns.    Sigh.. I just need to get more life out of the rears and hope local stocks get in soon.  Either that or just take a gamble on the new BS Potenza Sport for the rears.

Edited January 20, 2022 by Liongolfer

[Liongolfer]

On 20/01/2022 at 15:59, Andrea said:

 

with the /30 I'd worry more about you overall diameter which is 6.5% smaller than stock.  That might mess up with the PSM. Also it will sit your car another 20mm lower at the rear. (not to mention you'll reduce the rake angle of the whole car.

 

285/35 is a much closer to stock and preferred.

 

Regarding width, there isn't just one answer fits all. This depends on how much negative camber you are currently running, rim offset and rim width.  If you post those specs then it's easier to work it out by using a simple online tool: https://www.willtheyfit.com/

 

Another thing to consider is your car will tend to understeer more if you only widen the rear and not the front. 

 

 

 I got a pair of 265/40/18 BS Potenza Sport mounted today.  Obviously too soon to see how they compare to the PS2s.

 

Just a note of thanks for chiming in and for your knowledge share.