What offset for a 285 on the front?
Thread Starter
Tech Contributor
Joined: Oct 2008
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From: Custer, WI
What offset for a 285 on the front?
I'm planning on ordering some Forgestar CF5's, and want to run a 19x11 rear, with an 18x10 front. They are custom built so I'm curious if anyone is running a 285 or something close on the front.
My car is an 85, stock offsets were 32 for standard and 38 for Z51 if i'm not mistaken. Can I just run 36mm like the ZR-1 wheels?
Thanks in advance,
Jeremy
My car is an 85, stock offsets were 32 for standard and 38 for Z51 if i'm not mistaken. Can I just run 36mm like the ZR-1 wheels?
Thanks in advance,
Jeremy
Team Owner
Joined: Sep 2003
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Have you had 11 @36 on the rear already?
No experience with an early car but 10 @32 would duplicate the 'inner' clearance that's present with the 9.5 @38.
What do you have on the fronts presently? Do your comparisons from what is 'known' to you!
No experience with an early car but 10 @32 would duplicate the 'inner' clearance that's present with the 9.5 @38.
What do you have on the fronts presently? Do your comparisons from what is 'known' to you!
Thread Starter
Tech Contributor
Joined: Oct 2008
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From: Custer, WI
Haven't ran that big of a tire on the back yet, just stealing the offset from the ZR1 wheel that apparently just bolts right on to the early C4s.
I have C6 oem wheels on the car now, but they require adapters. The front is a 245/40/18. Back is 285/35/19
I have C6 oem wheels on the car now, but they require adapters. The front is a 245/40/18. Back is 285/35/19
Last edited by Pwnage1337; Feb 12, 2018 at 02:50 PM.
Team Owner
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If you like the tire placement as it is now then use the offsets of those wheels + the thickness of the adapters for the calculations. On the rear I'd put my hands on a 11" @36 from a ZR-1 and do a test fit!! You're going to be the guy who's committed for the $$$ once they're built.
I think an 11@36 would require the rear be spaced equally on both sides. All C4's ain't that way!!
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From: Overland Park Kansas
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I've always found this calculator helpful in visualizing current vs future offset/size/diameter changes.
https://www.rimsntires.com/specspro.jsp
https://www.rimsntires.com/specspro.jsp
Thread Starter
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
I've always found this calculator helpful in visualizing current vs future offset/size/diameter changes.
https://www.rimsntires.com/specspro.jsp
https://www.rimsntires.com/specspro.jsp
I'll give it a shot later. Maybe their server is down.
Thanks everyone so far for their input
Jeremy
