I like 245/60-15 front and 255/60-15 rear with 7in rims. 255/60-15 front and 275/60-15 rear if 8in rims....if stock height....otherwise fronts will rub.
You can trim back the fender lip to gain some clearance. I could have told you that 5" wasn't enough back space for the 10" wheel. 5 1/2-5 5/8" is what it takes. Most cars have more room on one side than the other because the body isn't exactly square to the frame.
Yeah only rubbing on one side. The specific wheel does not come in a greater than 5". Bummer. Hey thanks for the quick reply. I went with the same Rallye by Coker but the 15x10. Looks awesome. I guess if Coker won't let me return them I will trim the wheel well a bit. I also will be ordering a new rearend in the next year and I may be able to reduce the overall width by an inch or two.
You could have gotten the increased back spacing, but you would have had to special order it and pay more. I have 15 X 8" Buick wheels with 275 in the rear. Back spacing is 4 1/2". It is close on one side. I could actually use 5" BS on that one side. Once you mount a tire on the wheel, it is unlikely they will take them back.
Looks great guys! But, the original question was about 15 X 7" wheels. A 295 tire needs an 8" or wider wheel. Pretty sure the wheels pictured are wider than 7".
But going back to the original question, what are the biggest tires you can put on 15x7" rims? I have a '71 Riviera. The original 6" rims have 215/75R15 tires, and there is loads of room in the wheel wells all around. I'm now switching to some early 1980s 15x7 rallys. Could I go something like 255/70R15 in the rear, and 235/70R15 in the front? Does the GS have less room in the wheel wells than the Riv, b/c you guys don't seem to mention anything bigger than a 50 or 60 aspect ratio. I am almost positive 235/70 would work, b/c as I understand it they would only sit slightly higher than the 215/75s that are on there now (though it would definitely be a lot wider). I greatly appreciate any and all input. Thanks very much. Dave
You can run a 255 section width tire on a 7" wide rim with no problem at all. Your current P215/75R-15 tires are 27.7" tall. The P255/70R-15 is 29" tall. A P235/70R-15 is 28" tall. The 255 tires are 40mm wider than the 215 tires, that's about 1.6", or .8" on both sides of the tire center line. Being that you are going to 7" rims from 6" rims, I would measure the back space on both. That would be the only variable to check. The Big Car 6" wheels had either 3 3/8" or 3 7/8" back spacing depending on year. The Big car 7" wheels had 4 1/4" back spacing. There could be as much as 1/8"-3/8" difference in centering of the wheel in the wheel well.
Larry, Thanks very much for the reply. I knew you would know the answer! I get closer to 4.5" of backspace when I measure the 7" rims, but they are rim code 011 (from 1980, '83, and '85), so I am almost positive they are the rims you show as 6th generation on the 15(5x5) chart. Also, I know the bolt pattern is right and they fit over my brakes front and rear. I will have to pull the 6" rims and check the backspacing. I can't promise I won't have more questions after I do so! But one more question for now--assuming that backspacing is not an issue, can I go wider than 255 on the 7" rims (at least for the rear)? I'm not looking to push the envelope here, so want to keep it safe. Thanks again. Dave
I wouldn't, a wider tire really wants an 8" or wider rim. I have 275's on the back of my GS on 8" rims. You can put them on 7" rims, but it really isn't advisable.
I always ran 245/60R15's all around but last build I went w/235's and was very pleased with look & performance.
