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Offset question ITS Guys running 225's on 7 inch rims

Old 11-04-07, 01:53 AM
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Offset question ITS Guys running 225's on 7 inch rims

What offset do you guys run?
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Old 11-04-07, 06:17 AM
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Mine are ATS Comp Lites 15x7 with 35mm offset. I have two sets - Toyo RA-1s and Kumho V710s 225/50, neither rub at all.
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Old 11-04-07, 07:10 AM
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35mm offset 15 x7 with 225/50/15 and I have to use a 1/2" aluminum spacer and ARP studs to get about .25-.375" clearance from the spring seat. Wheel was not available in less than a +30 anyways. Suspension is strut tubes and spring seats from AWR. My spring seat sits about in the middle of the tire.
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Old 11-04-07, 08:17 AM
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effective offset is then +22,+23?

How's the tramlining on the car? I currently have a set of +24 or +25 rims.
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Old 11-04-07, 10:47 AM
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It'll depend on the suspension used, but from what I've read you typically need a mid to high 20's offset to clear Hoosiers when using something like Konis or KYB's and GC's.
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Old 11-04-07, 10:54 AM
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Originally Posted by Roen View Post
effective offset is then +22,+23?

How's the tramlining on the car? I currently have a set of +24 or +25 rims.
That should be just fine. I would probably have purchased +25 if available. Tramlining is not an issue for me. As a point of reference the stock 15 x 6.5" BBS vert wheels are a +40
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Old 11-05-07, 02:08 AM
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I guess the smooth paved surface is much different than the streets outside. What's the widest offset you've seen that still keeps the tire within the fender?
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Old 11-05-07, 07:23 AM
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Originally Posted by Roen View Post
I guess the smooth paved surface is much different than the streets outside. What's the widest offset you've seen that still keeps the tire within the fender?
I think you mean least positive offset, if you are constructing under IT rules the exact verbiage is below. I have not rolled mine through a powdered substance but can say when viewed from above, the bottom of the tire does protrude beyond the fender. This is because of 3.5 degrees of camber, I would guess the tire tread in static conditions is too close to call and any less offset would make it illegal. Pictures below...

IT rules.. "Tire tread (that portion of the tire that contacts the ground under static conditions) shall not protrude beyond the fender opening when viewed from the top perpendicular to the ground. To determine compliance, the vehicle should be rolled through a powdered substance, as raced with driver, in order to indicate the tire tread contact patch under static conditions."

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Old 11-05-07, 08:49 AM
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quick question, how much do those wheels weigh?
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Old 11-05-07, 09:06 AM
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Originally Posted by Roen View Post
quick question, how much do those wheels weigh?
I do not recall exactly and the site says from 6.1kg at highest offset. Mine are +35 Anthracite, they told me they could not drill a 5 x 4.5 pattern on a this wheel with less than +30

http://www.teamdynamicsracing.com/pr...race1black.htm
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Old 11-05-07, 09:14 AM
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nice looking wheels! I'm just running standard mustang wheels, 16.1 lbs, if I'm correct.
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