17" Cup Options
#1
Drifting
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I have to replace my tires. Looks like the Sumitomos are the way to go. I searched but didnt find the answer to this although i am sure it is in here somewhere.
If i want to keep the stock rims and go with wider tires than the 205/255 purely for cosmetic reasons, what is the most practical upsize? And are there any downsides to this? Should I just stay with the size i have now? This is a street car only and has been lowered (dont know if it is ROW, RS height or what as it was done by the PO).
Thanks
If i want to keep the stock rims and go with wider tires than the 205/255 purely for cosmetic reasons, what is the most practical upsize? And are there any downsides to this? Should I just stay with the size i have now? This is a street car only and has been lowered (dont know if it is ROW, RS height or what as it was done by the PO).
Thanks
#2
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Fronts are easy, a 225/45-17 will fit the 17 x 7 wheel fine.
Rears are a bit more tricky because you will more than likely have an effect on overall gearing. 275/40-17s would probably be fine on the 17 x 9 rear but would make your gearing taller. Not desireable in a car who's gearing is already too tall (IMO).
If it were me I'd go with 225/45-17 front and stay with 255/40-17 rear. If you track or auto-x this should reduce understeer slightly as well.
Rears are a bit more tricky because you will more than likely have an effect on overall gearing. 275/40-17s would probably be fine on the 17 x 9 rear but would make your gearing taller. Not desireable in a car who's gearing is already too tall (IMO).
If it were me I'd go with 225/45-17 front and stay with 255/40-17 rear. If you track or auto-x this should reduce understeer slightly as well.
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Remember the "40" is an aspect ratio. A percentage of the tread measurement. So by increasing your width and staying with the same aspect ratio you're getting a (slightly) taller tire.
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#11
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I ran the 205 and 255 stock combo; they worked great. Porsche engineers figured the optimal tires sizes out....they plenty smart over there. Just stay with stock....you are not tracking the car...they'll be fine...and cheap too!
#12
Drifting
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it was going to be purely for cosmetic reasons not track. i just prefer the look of wider tires and was trying to find something that would work
thanks
thanks
#13
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Cosmetics....now we are talking. My car is all about cosmetics. See Grand Prix white NB 993 covered in Blue Painters tape.
235/45/17 front and 275/40/17 rear...this is the combo I use from Toyo with their RA-1 tires...of course these fronts are NLA from Toyo![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
You need to exercise caution on the rolling radius delta front to rear. You cant just ***** nilly put a set of random tires on your car. The front to rear rolling radius delta should not exceed 3%. If you e-mail me mfschacht@gmail.com, I will send you an EXCEL spread sheet that allows you to calculate the delta in a matter of seconds. This offer extends to any and all.
The consequences of a rolling radius delta mismatch front to rear, the ABS will shut down. You do not want this to happen. And I agree, Big Meat looks cool.
235/45/17 front and 275/40/17 rear...this is the combo I use from Toyo with their RA-1 tires...of course these fronts are NLA from Toyo
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
You need to exercise caution on the rolling radius delta front to rear. You cant just ***** nilly put a set of random tires on your car. The front to rear rolling radius delta should not exceed 3%. If you e-mail me mfschacht@gmail.com, I will send you an EXCEL spread sheet that allows you to calculate the delta in a matter of seconds. This offer extends to any and all.
The consequences of a rolling radius delta mismatch front to rear, the ABS will shut down. You do not want this to happen. And I agree, Big Meat looks cool.
#14
Rennlist Member
![Smile](https://rennlist.com/forums/images/icons/icon7.gif)
Cosmetics....now we are talking. My car is all about cosmetics. See Grand Prix white NB 993 covered in Blue Painters tape.
235/45/17 front and 275/40/17 rear...this is the combo I use from Toyo with their RA-1 tires...of course these fronts are NLA from Toyo![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
You need to exercise caution on the rolling radius delta front to rear. You cant just ***** nilly put a set of random tires on your car. The front to rear rolling radius delta should not exceed 3%. If you e-mail me mfschacht@gmail.com, I will send you an EXCEL spread sheet that allows you to calculate the delta in a matter of seconds. This offer extends to any and all.
The consequences of a rolling radius delta mismatch front to rear, the ABS will shut down. You do not want this to happen. And I agree, Big Meat looks cool.
235/45/17 front and 275/40/17 rear...this is the combo I use from Toyo with their RA-1 tires...of course these fronts are NLA from Toyo
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
You need to exercise caution on the rolling radius delta front to rear. You cant just ***** nilly put a set of random tires on your car. The front to rear rolling radius delta should not exceed 3%. If you e-mail me mfschacht@gmail.com, I will send you an EXCEL spread sheet that allows you to calculate the delta in a matter of seconds. This offer extends to any and all.
The consequences of a rolling radius delta mismatch front to rear, the ABS will shut down. You do not want this to happen. And I agree, Big Meat looks cool.
#15
Drifting
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Martin, are the 235/275 combo on your standard Cup rims? Any adverse effects?
I had considered going to 18's but i couldnt honestly find another set of rims that i liked that much more than the Cups to spend all that extra dough.
Therefore will likely stay with the Cups and new tires and get the Cups refinished
thanks
I had considered going to 18's but i couldnt honestly find another set of rims that i liked that much more than the Cups to spend all that extra dough.
Therefore will likely stay with the Cups and new tires and get the Cups refinished
thanks