18 inch RFT choices - other than Michelin or Bridgestone or preference?

Spazdoc · 03-08-2009, 06:48 PM

I need to choose new tires due to wear of my stock Sport package RFT and now that I have wider wheels. I am looking for 225/40/18 to go on an 8.5 inch front and 275/35/18 to go on a 9.5 inch rear. The only choices that I can still find are Bridgestone Potenza RE050A RFT and Michelin Pilot Sport PS2 ZP. I am not giving up summer RFT under any circumstance, since these need to be reliable in case my wife is driving with kids in the car.

I have seen the other threads, but I was hopeful that someone knows of another choice or has a preference of one over the other.

The Michelins seem to be preferred, but are these the only non-RFT choices?

NinetyEight740 · 03-08-2009, 07:46 PM

why do you want to run a 275? i would run a 275/30R18 otherwise your circumfrence is gonna be off...

Spazdoc · 03-08-2009, 08:51 PM

255's are not quite wide enough for 9.5 in wheels - they look stretched. Additionally, I could not find 265 width RFTs in 18in.

The 275/30/18 is 0.5 inches smaller in diameter than the 255/35/18, while the 275/35/18 us 0.5 inches larger. Additionally, there are no 275/30/18 either Bridgestone or Michelin RFT.

Thanks for the input.

Orient330iNYC · 03-08-2009, 09:34 PM

Quote:

Originally Posted by NinetyEight740

why do you want to run a 275? i would run a 275/30R18 otherwise your circumfrence is gonna be off...

275/30/18 will be off by -2.5%
275/35/18 will be off by 1.9%

235/40/18 up front would be a better match to 275/35/18... thats off by 0.7%

Spazdoc · 03-08-2009, 11:06 PM

The difference is actually closer than that. Unless I am doing it wrong, using two different tire sizing calculators, the 275/30/18 will be 2.12% smaller, while the 275/35/18 will be 2.16% larger.

Firgured that if I flash the ECU, the car can handle the extra tire diameter. Additionally, since the speedometer already gives a 5 mph compensation, I can afford the 1.2 mph bump.

03-08-2009, 06:48 PM	#1
Spazdoc Major 42 Rep 1,218 Posts Drives: 2020 C63S, 2001 S4 Join Date: Jan 2007 Location: Earth iTrader: (9) Garage List 2007 335i [0.00]	18 inch RFT choices - other than Michelin or Bridgestone or preference? I need to choose new tires due to wear of my stock Sport package RFT and now that I have wider wheels. I am looking for 225/40/18 to go on an 8.5 inch front and 275/35/18 to go on a 9.5 inch rear. The only choices that I can still find are Bridgestone Potenza RE050A RFT and Michelin Pilot Sport PS2 ZP. I am not giving up summer RFT under any circumstance, since these need to be reliable in case my wife is driving with kids in the car. I have seen the other threads, but I was hopeful that someone knows of another choice or has a preference of one over the other. The Michelins seem to be preferred, but are these the only non-RFT choices?
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03-08-2009, 07:46 PM	#2
NinetyEight740 Major General 231 Rep 5,691 Posts Drives: 2 - 2013 535i msport Join Date: Nov 2008 Location: Orange County California iTrader: (2) Garage List 2010 E91 [0.00]	why do you want to run a 275? i would run a 275/30R18 otherwise your circumfrence is gonna be off...
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03-08-2009, 08:51 PM	#3
Spazdoc Major 42 Rep 1,218 Posts Drives: 2020 C63S, 2001 S4 Join Date: Jan 2007 Location: Earth iTrader: (9) Garage List 2007 335i [0.00]	255's are not quite wide enough for 9.5 in wheels - they look stretched. Additionally, I could not find 265 width RFTs in 18in. The 275/30/18 is 0.5 inches smaller in diameter than the 255/35/18, while the 275/35/18 us 0.5 inches larger. Additionally, there are no 275/30/18 either Bridgestone or Michelin RFT. Thanks for the input.
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03-08-2009, 11:06 PM	#5
Spazdoc Major 42 Rep 1,218 Posts Drives: 2020 C63S, 2001 S4 Join Date: Jan 2007 Location: Earth iTrader: (9) Garage List 2007 335i [0.00]	The difference is actually closer than that. Unless I am doing it wrong, using two different tire sizing calculators, the 275/30/18 will be 2.12% smaller, while the 275/35/18 will be 2.16% larger. Firgured that if I flash the ECU, the car can handle the extra tire diameter. Additionally, since the speedometer already gives a 5 mph compensation, I can afford the 1.2 mph bump.
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