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Discussion Starter #1
I'd like to put as larger a set of rear tires on '67 GTO (currently have 225/70-15's). I am using 15 x 7 Rallye II wheels. Does anyone know if 245/60-15 or 255/60-15 tires will work OK on the rear? Front is lowered ~2" and has 225x60-15's. :)
 

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With the stock backspace they will not fit. You will need at least 5" backspace. I have 225/60/15 7" rallye II on the back of mine and they are fine.
 

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I am doing some work on a nice 1967 GTO Post car...
the guy wants a stage 2 Hotchkis suspension under it and rear disc brakes...
Problem is that it has stock 14x6 Ralleye II wheels on it and the SSBC brakes that I put on the rear rub. So I am going to upgrade the wheels with some 15" Ralleye IIs. Just wanted to see if anyone has done any 15X8 wheels on one... and what the backspacing was... I could always go with a 15X7... but still would like to know what backspacing... want to do a 235/60 15... Any input on the matter would help me out a lot. Thanks in advance.
 

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Discussion Starter #4
Hi, novafreak69

I now have 245/60 X 15's on the rear of my '67, mounted on 15x7 Rally II's. The wheel backspacing is 4 1/2" and the tire fit is very close on the outside - inside is fine. I had wanted 255/60x15's, but 245's are the widest recommended size on 7" rims, so the best solution would be new 15x8 wheels with a 5" backspacing.
 

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Discussion Starter #5
Continued response to novafreak69 -
While getting to the point where I am, I looked into whether I might get the 15x7 Rally II's widened to 7 1/2 or 8". That got me looking into where the interference would be with 255's. At first I thought it was the lip at the wheel opening in the fender - figured that I could do some carefull trimming back to reduce the flange from 1+ inch down to ~3/4" and it would be OK. Upon further review..... there is a part of the inner fender wheel 2 - 3" above the opening that curves in toward the center of the car and back out again - a sort of formed bulge that is probably there to stiffen the fender well(?). I entertained the idea of slitting this area - pounging it flat (or at least less of a bulge) and re-welding. Decided against all of the above, but thought I'd share...
By the way - my car is now lowered ~1" in front with front discs and 225/60x15's. The rear has 1" spacers under old springs, so I'm about 1/2" high at the back.
 

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tires

I run 245 60 r15's Rally II 7's all the way around on our '66 Lemans convertible- stock drum brakes, new springs. No issues, no rubbing. G.
 

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TommyG67...

I would like all the wheels and tires to be the same size so that he can rotate them. I am not sure what the standard BS on a 7" Rally II is... I am leaning towards a 235/60/15 on a 7" Rally II BUT... the current 14"X6" rally II are pretty close on the outer lip in thee back... and I do not want to change the stance of the car or cut on it...
 

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On my 67 lemans be fore the rebuild I had 15x8 weld pro stars. 225/15 on front with a 4.5 bs on front and a 275/60/15 drag radial on the rear with a 5 or 5.25 (not sure have to measure again) on the rear. The only difference is I have a 68/69 12 bolt which is about a 1.5 inches wider than a stock 10bolt so my backspacing would be a little more. But it's possible to fit a wider tire with the right bs. Going to buy myself new wheels for Xmas. Prob ridler 695 245/45/18 front with 4.5 bs and 275/40/18 with 5.5 bs on rear. Going to put the body on the frame on sat to double check the measurements for the rear to make sure they fit.
 

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Running 275x60x15 on vintage 15x7 rally's. No clearance issues at all...:cool
 

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i have 15 x 8 with 5 inch backspace running 275/60 on rear.....15 x 7 with 4.5 inch back space runs 235/60 on front no issues, tried 245 on front it rubbed
 

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Well, I was wrong, the factory 7" wheel has 4" backspace at the bead and 4 1/2" at the lip. I took a few pics to show where I measured from.
First is at the bead...4"



Second is the overall setback of the tire... almost 5 3/4" This is the distance you need to know for clearance anyway. Having a narrower tire will provide more backspace. I couldn't get the camara down level on these pics to accurately show the measurement.



Third, you can see how much sidewall bulge is present with the 7" wheel. This will straighten up quite a bit with an 8" wheel.



I put this on the car to check for fender and frame clearance. Tire to frame is 1 1/2"



Tire to inner wheel well is close...1/2"
The 275x60x15's I have are on another car, a 1966 Chevelle and they are close but don't rub. It is 30 miles away in storage for the winter. Adding another inch to the wheel width and going with the 5" backspace that fiesta62 has should be good. If in doubt, consider a 255x60 tire but be aware that it is almost 2" shorter than a 275x60

 

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I test fitted a 15X8 Corvette rally on the car with a MT 275/60 Drag Radial... and there is no way the outside lip would not rub... I had about 2.5 inches to the inside frame rail. The guy wants to be able to rotate the tires..so different offsets on front and back wheels is a No Go. I think the 15X7 wheels with 245/60's will work on the front and rear... and still be stock appearing and not rub in the front or back....and not rub the aftermarket disc brakes in the rear......
 

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A corvette wheel has a shallow offset....more wheel to the outside. Either way, if he wants to rotate tires, he needs to stay with a 235x60. They will rub slightly on the frame at full turn in front and a 245 will rub big time.
 

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A corvette wheel has a shallow offset....more wheel to the outside. Either way, if he wants to rotate tires, he needs to stay with a 235x60. They will rub slightly on the frame at full turn in front and a 245 will rub big time.
THANK YOU... That is what I was wondering... :) Wheels and tires being orderd today! Thank You EVERYONE for your input on this project... I will post some pics on the forum when I finish this project. Car is pretty good shape.... Original Texas car from what I understand...

67 GTO post car. 400 w/automatic and Air.

Someone put the tri power intake and carbs off a 66 on this engine.... I am doing the disc brake upgrade, fixing some leaks.... and doing a Stage 2 Hotchkis suspension under it... and wheels and tires...
 

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Looks good......nice stance and the tires are wide enough to add attitude.:cool
 
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