72 skylark currently running 235 60r all around...the rear sits a little low or my taste. At the swap meet Sunday I saw a 72 chevelle with a real bad lookin stance...he had 275 60rs on the rear and 235s on the front. Couldn't get much info outta the guy cause he was like 90 and kinda delirious to which car was actually his haha. But anyhow he said if he remembered thy were 15x7 wheels. Anybody have any pics or info as far as 275s on the rear. Any wheel rub? Could they blow off? It looked like the sidewall was almost Double the 235s
275/60s on 8" rim will work just fine. Have used them and 235/60s on the front. Makes for a nice stance on a '70.
No pics but I know a few board members run them on 15x7 no problem. They will balloon a bit. I plan on running them with 15x7s
My car had 275/60 on a 15x7 when I bought it. They will fit, but you can see where the centers were wearing due to the narrow wheel. They would better on a 15x8, but you can do it. Brandon
My car has 15x7's with 275 60 r15 tires. For the rubbing risk it's real close on the outer lip for my taste but that is because my rims (taken from another car) don't have the appropriate backspacing for my 64 Special. There's plenty of room for the width, just needs to have more offset.
I run a 235/70 on the back 235/60 on the front for my cruise setup. 235/70 is a 28" tire, same as 275/60. Drives nice and the stance is just right for my 70.
A 255 is not wider than a 275. That first number is the tire width. So the larger that first number, the wider the tire. The second number is an aspect ratio of the first number, which indicates the height. So a 275/60/15 is 275 millimeters wide. 60% of 275 millimeters is the height. Brandon
So 275 70s would have a larger sidewall then 275 60s? I just looked up the overall width of the 255s and it was larger then the 275s...I'm new to determining tire sizes and what the number really mean that was a big help and really helped me grasp the concept a bit
Example: P275/70R15: The 275 is tread (tire) width in millimeters. The 70 means section height is 70% of tread width, so section height is 275 x 0.7 = 192.5 mm. Devon
Actually, it is section width. The tread width can vary with tire design. Section width is the width across the tire from sidewall to sidewall. The number after P in P275/60R-15 is the section width in mm. 275 mm can be converted to inches by dividing by 25.4mm/inch. That would be about 10.8" The tire section width can also vary with the rim it is mounted on. A wider rim will increase the section width by a small amount. You can easily figure out the height of any P metric tire with a calculator. The aspect ratio is the size of the sidewall in relation (%) to the section width. For a P275/60R-15, convert everything to mm, then divide by 25.4 to get inches. The 15" rim would be 15 X 25.4 =381 mm. The side wall would be 60% of 275 or 165 mm. double the side wall + rim = tire height. 2(165) + 381 = 711 mm/25.4 = 27.99" A P255/70R-15 would be 2(178.5) + 381 = 738 mm/25.4 = 29.05" tall
On a 70-72 Skylark/GS, it will easily fit. We are talking about the stock 15 X 7" Buick factory wheels, correct? As mentioned, the 7" wide rim is not optimal for a 275 tire, but lots of folks do it, and it will work.
Nah I have your basic vet style ralley 15x7 4.5 backspacing(I think) how much bigger can I go? With the 235 60s on the front I want a big tire to give it a nice jacked up stance in the rear
275 is as big as I would go with a 7" wide rim. Don't think about back spacing. Take a wheel off and measure. Lay the wheel face down and measure from the wheel mounting surface to the bead surface of the rim. 4 3/8" minimum is required.
You're welcome Devon. I always rely on you to catch my mistakes. It's only right that I should try to do the same for you:TU:
I have the N25 bumper on the rear and when I ran 275's they rubbed the exhaust (2.5 inch club exhaust with the x pipe). Looked good but hard cornering would cause them to rub the tire so I went with 255's with no issues.
