will having a larger tire outback cause understeer?

blksgZ28 · 07-03-2002, 01:51 AM

I want to step up to a 255 tire up front, but I currently have 275 for outback. This is probably the best I cna do for now becuase of my rim sizes(17x8.5 up front and 17x9.5 out back), but my next set of tires will be 17x10 all the way around msot likely. What can I do to counteract any understeer(if any) that may occur from this?

Elliswon · 07-03-2002, 11:59 AM

Any or all of the following:

More negative camber up front, stiffer springs or bar in the back.
Air pressure adjustments front or back.

blksgZ28 · 07-03-2002, 01:19 PM

so then I will most likely see some understeer with the difference in tire size?

Norm Peterson · 07-03-2002, 07:25 PM

As I understand things, you currently have a tire that's NARROWER than 255 up front. Moving up to the 255 will probably increase front grip slightly (LESS understeer than what's current) but with slightly softer turn-in.

I guess the next question is what size tires are intended for the 17 x 10 wheels? 275/40's all around?

Norm

[This message has been edited by Norm Peterson (edited July 03, 2002).]

blksgZ28 · 07-04-2002, 12:50 AM

yeah, I'm about to put my new wheels on, but the front's need new rubber(the backs have 275/40 on 17x9.5 rims, about 90% tread left), currently the car has the stock 245's on 16" rims all the wya around, and the 17x8.5" rims have 245/35/17, which is really small compared to the stock ones. I was told I could fit 255 up front, so I'm going to try that, and see how it works out. Actually, What I really want is some 18" rims now that I'm thinking about it, but still debating on width atm. I'm going to pay quite a bit ofr these(fikse fm5) so I want to get them right the first time. I may even try to fit 18x11 up front and 18x12 outback.

FRDEATR · 07-10-2002, 05:41 PM

Just to answer the topic, I don't think that having a larger tire will cause more understeer, but rather lessen the oversteer since you have more traction in the back. Hope this helps,

Brian

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Black 1994 Z28, M6 conversion complete. Eibach Pro-kit, Bilstiens, Chrome 17x11 ZR1 rims, LS1 Brake Upgrade, K&N CAI, AS&M Headers, High-flow Cat, B&B Tri-Flo W/ Quad Tips, Cutout, B&M Ripper, McLeod Street Twin, Kenny Brown DD Subframes, More to come...

There Goes the Neighborhood!!!

Eric Bryant · 07-12-2002, 03:57 PM

If switching to larger rear tires, I'd recommend a bit more spring rate or swaybar to take full advantage of them, unless you're right on the limit (or over!) with the current setup. Of course, a lot would depend on driving style and power, and everything depends on how the car handles right now.

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1996 Impala SS - LT4 396, T56
1996 GMC K2500
1992 Buick Roadmaster Estate Wagon