235/40R17 tires and stock rims.

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DavidD339
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Joined: Sat Nov 04, 2017 3:16 pm

235/40R17 tires and stock rims.

Post by DavidD339 »

Can I use 235/40R17 tires with the stock 17X7 rims or do I have to move up to a 17X8 rim?
DanielS172
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Joined: Mon Jul 25, 2016 7:09 pm

Re: 235/40R17 tires and stock rims.

Post by DanielS172 »

I don't have much experience with fitting tires, so they may physically fit, however you probably wouldn't want that setup. I believe the MX-5 Cup cars (NC) ran a 225 tire on the stock 17x7s, and that's probably the upper limit. When you have that wide a tire on that narrow a wheel, the turn in crispness will be crap. I think for 235 you'd want to go at least a 17x8, if not 9. Just my .2 cents.
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Brian
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Re: 235/40R17 tires and stock rims.

Post by Brian »

That 235/40 is VERY SLOPPY on 7 inch wheel, we typically use 17x8 for street use of that size, and 17x9 for track use of that size to better stabilize and support the sidewall.
Brian Goodwin
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DavidD339
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Joined: Sat Nov 04, 2017 3:16 pm

Re: 235/40R17 tires and stock rims.

Post by DavidD339 »

Thanks Brian and Daniel, I kind of figured that would be the case.
LAMike
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Joined: Wed Aug 09, 2017 11:06 pm

Re: 235/40R17 tires and stock rims.

Post by LAMike »

The math works out as well for going to 8" w/235. The 235 is 15% wider than the stock 205, and the 8" wheel is 15% wider than the stock 7". Indicates some parity. I'm running 235 x17" on 6ul 8". Very nice.
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