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255-70-15's for rear on 71 RR?

Christopher

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Last year I put 255/60/15's on rear of my 71 RR with some 15x7 TTO's. After looking at it, I'm really wondering if I could go with 15x8.5's and 255/70's in the back?

Has anyone tried the fitment of 255/70/15's and a 15x8.5 wheel with a 3.75 back space (or keep 15x7 and go with 255/70)?

Thanks
Chris

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I would go wider (275 or 295) with the same aspect ratio(60) rather than taller with the same width.
 
I would go wider (275 or 295) with the same aspect ratio(60) rather than taller with the same width.


275/60/15 is largest I'd think of going, but requires a 15x8.5 minimum, and since I can only get a 3.75 offset, I'm not sure they will work. I'm looking for taller to fill the wheel wells, hence thinking of 70 series in the back.
 
I have 255/70-15 on the back of my 62 savoy, on 15x8 steelie. I chose them for height, to fill visually the ridiculously long wheelwells. The backspace you are talking about on the 8 1/2 rims would never work on my car, or most anybody else's b-body that ISN'T a fuselage body. It MAY work on yours.
I just measured mine. On a 8",4 1/2 bs, 28 1/2 tall, 8"tread on the ground, 10 3/4 section width. They would work fine on your sevens but might not be close enough to the fender to visually fill the wheelwell. I'm guessing that's what you're trying to do. ( by the way, mine are t/a radial absolutely hopeless at hooking up ANY horsepower, that's what slicks or drag radial are for).
 
I have a couple of sets of old "deep dish " mags that are almost worthless. Any tire wide enough to work on the rim, contacts the fender due to too little backspace.
 
The 275/60's look OK, but honestly, I'm not a fan of the lower profile. If I could get a 15x8 TTO, then thats probably what I would have done at the start. But, they only offer 15x8.5s for the TTO, and I thought they would probably bee too wide.

I went ahead and ordered a set of pair of 15x8.5's from summit to try out. Worst case that could happen is they don't fit I guess and send back.
 
Are the tto's offered only in that one backspace? I've got some tt2 that are 4.75 bs but i know they are 2piece. I dont know if my steelies are ramcharger or custom made.
 
Plenty of guys run 275 60 on 71 B bodies. A few have gone 295 with no issues
 
I had 275 60 R15 on 8 inch rim before on my 71 RR. Currently running 275 65 R17 on a 9 inch rim. Fills the wheel weel nice
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255/70/15 on 8" rim and 4.5bs. On my 71 with no issues. I like the 70 series tire because it fills up the wheel well a lot better than the 60 series tire. :2cents:

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Droptop, thanks. Exactly what I was looking for!

I agree that 70 series full the wells better. What are you running for fronts?
 
I would go wider (275 or 295) with the same aspect ratio(60) rather than taller with the same width.

actually getting wider will make it higher too with same "aspect ratio". The profile number is not an absolute number but relative to the width. So going wider will get higher too still with same 60 on height.
 
255/70/15's are my favorite for the rears, they don't look so short and flat on a wider wheel. , I have them on my 8 , 8 1/2 and 10 inch wide wheels
 
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