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stevedollar · 11-20-2010, 01:46 PM

Beware that if you mix tire sizes front and rear (so there is more than 1% or 2% variance front to rear) your ABS will not work properly and your brakes will feel like they are not fully operating. I bought some wheels that had newish tires mounted on them, but the rears were 4% taller than stock. That was enough of a difference to make it so that the brakes felt like they were pushing back and not being fully applied when I took a freeway exit. Around town it made no difference. The Porsche dealer suggested reinstalling the old wheels and tires before bringing the car in, and sure enough, everything was back to normal. I ended up going to the tire size calculator on Miata.net and getting OEM size tires for the different sized wheels I had bought and everything is fine now. Good luck. PS the Michelin Pilot Sports are great. :dance:

11-20-2010, 01:46 PM	#8
stevedollar Registered User Join Date: Nov 2010 Location: United States Posts: 1	beware of wrong sized tires - will mess up ABS Beware that if you mix tire sizes front and rear (so there is more than 1% or 2% variance front to rear) your ABS will not work properly and your brakes will feel like they are not fully operating. I bought some wheels that had newish tires mounted on them, but the rears were 4% taller than stock. That was enough of a difference to make it so that the brakes felt like they were pushing back and not being fully applied when I took a freeway exit. Around town it made no difference. The Porsche dealer suggested reinstalling the old wheels and tires before bringing the car in, and sure enough, everything was back to normal. I ended up going to the tire size calculator on Miata.net and getting OEM size tires for the different sized wheels I had bought and everything is fine now. Good luck. PS the Michelin Pilot Sports are great. :dance: