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Discussion Starter · #1 ·
I have a 67 fastback GT S-code that I've had for about a year. It came with American Racing Vectors with 14x7 w/245/60R14 (4.0"backspacing) and 16x10.5 w/265/50R15 (3.75"backspacing). These wheels stick out in the rear a bit but there is no rubbing anywhere.

I have done as much homework as I can as far as fitment for new wheels and tires, but the amount of $ for new ones is tough to swallow without the expert opinions of you guys. I am a Newbie and am so grateful to have this community's combined experience.

I am looking to buy Coys C-5's in 17x8 (4.5"BS) and 18x9.5 (5"BS). BF Goodrich tires in 245/45R17 and 275/40R18. I know that my rearend is not stock because axle width and brakes all seem to be different. I have measured everything and have all existing spacing compared to the what the new spacing will be.

My question is, WILL THESE NEW WHEELS WORK AND BE ACCEPTABLE?

*MEASUREMENTS*
-front tire measurements should be fine as my stock front suspension and wheel and tire choice fits Dodgestang's Chart's recommendations (thanks so much Dodgestang).

-new tire diameter will be just over an inch larger but this should be ok.
-clearance on the inside of the tire to wheel well and to the leaf springs will be reduced from 2" to 0.75". IS THIS OK?
-Wheel will stick out 1.75" inches less than existing ones so SHOULD JUST CLEAR FENDER?

I know this is lengthy, but I am out of the country and have no one else to ask but you guys?
Any help would be appreciated.
 

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paulstu said:
-clearance on the inside of the tire to wheel well and to the leaf springs will be reduced from 2" to 0.75". IS THIS OK?
I can comment on the clearance to the leaf spring.

With my setup, I have approx .25" clearance from the inner tire surface to the leaf and I have run into no issues whatsoever. At .25", it is close to the inner wheel well but at .75", you should be fine.
 

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Current cars include 1969 Mach 1 and 1970 Cougar XR7 convertible
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First, welcome to the Forum

Second, despite the fact that these cars were mass produced, there seem to enough production line variances that what may work for one may not work for another.

All that being said, from my experience and reasearch, it seems that 4.75" backspace on a 17x8 wheel is the target on a '67. Less, and you risk rubbing the outside of the tire on the fender/quarter on bumps and turns. I'm suggesting that with a 245 section front tire you will more than likely need to consider rolling the fender lips, especially if the front end is lowered any appreciable degree. Dropping to a 235 section tire in the front may give you that little bit of extra clearance.

Whatever you decide to do, let us know how it turns out. Oh, and pics are always appreciated around here!!
 

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Discussion Starter · #4 ·
]Link[/url] ]Link[/url] ]Link[/url]

Here are some photo's of what I was talking about.
 

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I believe you may have done your math wrong.

It sounds like you are thinking 5bs minus 3.75bs equals 1.25bs change in position of the wheel....but you aren't taking into account the wheel width change. I believe you will be closer to a full 2 inch change in location based on some rudimentary analysis (at the min I know it will be more than 1.5 inch difference inbound...just not sure how much more because of section width difference...but prob close to 1.75)



Why don't you measure your rear flange to flange and look to see how it stacks up against stock...it look to me like you might be about an inch (maybe 1.5) wider than stock.

Also the important measure is clearance to the inner wheel housing...I don't know if you have enough clearance there. .75 clearance to the leaf is plenty of room..but I don't think you will have that much.
 
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