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Discussion Starter #1
I have the opportunity to buy a set of Cobra R replica wheels (17x8) and tires awfully cheap. I'm wondering if they'll fit my 67 Fastback with a 1" drop all around. I know the pattern will fit, I'm just worried about bottoming out, rubbing, and them sticking out from the fenders.

I have the complete Mustangs Plus Magna handling kit with 620 coils, new 4 leaf rears, Magna shocks, etc installed so i'm not expecting much mush in my ride. Will those 17x8s work with this setup?

Thanks,
Aaron
 

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It all depends on the backspacing and the tire size. I don't know what the backspacing is on a Cobra R wheel or the replicas you are looking at. Generally, with a 15" and maybe even a 16" wheel, you would probably run into some fender interference on an 8 inch wide rim since you are limited on backspacing (I think 4.5 inches max) due to the proximity of the in-board side of the wheel and tire to the upper control arm.

However, and someone please correct me if I'm wrong, you can have more backspacing on a 17" rim as the rim is big enough around to eliminate interference with the upper control arm. This means the wheel can have more backspacing and therefore fit further in-board thus eliminating fender clearance problems.

I would think you would want at least 5.5 inches of backspacing to be safe. The best bet is to test fit the wheels on your car with tire sizes you intend to use.

Tom Nash
68 Coupe, 5.0 EFI, 5sp
 

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I'm told by the tire experts that any spacer over 1/4" is not recommended, and any spacer over 1/2" is obscene (dangerous, even). I had a structural engineer (a buddy) look into the feasibility of spacers a while back, and with a few basic calculations, he agreed with the "tire experts".

Thespazardman
 
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I cut and pasted the spacing for the new factory GT premium wheels: [color:red]17" x 8", 4.5" inch bolt pattern with 5.72" backspacing. </font color=red>
I hope this helps. I don't think they will fit, but if you try them, and they work out okay, let us know. I think they would look great on my ragtop.

Chris Taylor

'67 Conv. 289 C-code Frost Turquise
'99 Ford F250 Super Duty 4x4
'01 Ford Escape (wife's car)
 

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I was looking into putting 1999 Cobra rims on my '68 CS/GT
coupe, but in the end decided against it. The cost of the adapters
was over $100 each. And they should be run on all four corners.
You run into some serious tracking problems without it.

If you use spacers, there is a serious danger of studs snapping
if they are over 1/4". But with adapters that bolt onto the original
wheel studs and then give you five new studs .... they are fine.
We have many people in our car club even running them on their
open track cars. (check out H&R springs web site)

I ended up going with Delta Bay Mustangs new Shelby 10 spokes
in a 16" x 8" size with the proper backspacing. Tires are on order,
will post pics when I get them mounted.
 
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