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Discussion Starter #1
Hi:

I have three sets of wheels:

17" 205/235 for winter
18" 235/265 for track
19 245/275 for street

Which set should I have on the car when I get it aligned? Is alignment affected by different width tires/wheels?

I will be going for max camber and zero toe in front.

Tomasz
 

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No brainer, track wheels I would think.

That's where the alignment is most critical.

And if alignment does change when changing sizes, they're in the middle also.
 

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Hi:

I have three sets of wheels:

17" 205/235 for winter
18" 235/265 for track
19 245/275 for street

Which set should I have on the car when I get it aligned? Is alignment affected by different width tires/wheels?

I will be going for max camber and zero toe in front.

Tomasz
I haven't calculated the front/rear height on these tire combos, but I'd answer as follows:

A dramatic difference from "baseline" in terms of the front to rear rake can cause a change in caster.

Beyond that, I don't believe the wheel/tire size can/will have an effect on alignment.

the other question that's important here is: in what scenario is the perfect alignment important to you? Track? Street?

finally, who are you having do your alignment? you're in seattle, right? I'd highly recommend tru-line or fordahl.
 

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Hi:

I have three sets of wheels:

17" 205/235 for winter
18" 235/265 for track
19 245/275 for street

Which set should I have on the car when I get it aligned? Is alignment affected by different width tires/wheels?

I will be going for max camber and zero toe in front.

Tomasz

Max Camber...Is less then 1 degree negative, I think, unless you get GT3 Lower Control Arms. That's why I got mine. I'm running just under 2 degrees negative camber on the front and my track tires still wear the outside edges. It's a compromise. I'd like to have it about 3 degrees negative and maybe 2.5 in back. It would eat the insides of the tires, but if you keep the toe at zero, it takes a while.

If you get big negative camber, the street experience can get a little exciting. ie front wheel braking is compromised. In back, you can spin the wheels a lot easier because the insides are biting harder than the outsides. Like having narrower tires. Deep into a high-speed turn, however, all is right with the world.

Big negative camber is not good for winter tires. They will work better with stock settings. You are fine with stock suspension set at "max negative camber". It doesn't adjust much.
 

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I'd go with the track tires. On the size issue isn't there a 4% rule out there? I read it and it indicated that the front/rear difference in diameter should not exceed 4% of stock.
That's what I used when I purchased my RE11's.
 

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The above points are all true. I'll add:
- Caster isn't adjustable on these cars anyway, and subtle rake changes wouldn't affect caster enough to worry about.
- Alignment is not affected appreciably by wheel or tire size - at least not in the range you're looking at. Heck, on racing cars, many times we align them with no wheels at all, using precise metal plates we call set-up wheels.
- As above, I think the most important is to decide what alignment settings you want, and then to choose a good shop to do the work.
 

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Discussion Starter #7
Thank you. That helps quite a bit.

Tomasz
 
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