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Discussion Starter #1 (Edited)
I'm working on a 67 tempest custom. Currently it has drums all around. When I can afford it; I expect to upgrade to disc brakes. I want to stick to the rally II wheels. I'm installing a 12 bolt chevy rear end in the next week. With that in mind; I'm looking for suggestions on tire and rim sizes. Thank you for your attention.
 

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Cosmetically, Anything bigger than 17' looks too big for these cars. I'd go for a 15-17 in the Rally IIs, can't go wrong. Are you looking for a performance tire for max traction, or skinnier stock replacement that just fits fine?
 

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Discussion Starter #3
I'm looking for something that looks stock; but has the clearance for upgraded brakes. This will be a driver; so I want to be able to rotate the tires. I believe 15 x 7; but I'm not sure about offset. If there are some date codes to stay away from. Also, I was told the rear end upgrade will widen the rear 3/8" each side.
 

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So you are using a later model 12 bolt? I'd recommend a Percy's wheelright to get the correct offset to ensure you don't have any rubb-age. I used it to fit my rears and I run a 12.5x29 street slick in the stock wheelwells.

Another thing to consider is the tire diameter, especially the front as they are known to rub the front edge of the fender when turning.
 

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Discussion Starter #5
The rear end reportedly from a 69' chevelle; I don't know if it is considered a later model.

Exactly, (tire size) this is why I'm looking for recommendations for both rims and tires.
 

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you will want a 4.5-5" offset on the rims for the biggest tires, max on the back is 275's and 235's on the front
 

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Discussion Starter #7
Thank you Instg8ter. Since I'd like to be able to rotate tires 235 on a 15 x 7 with a 4.5" to 5" offset is what I'll look for. As far as width goes; I assume 70 is ok.
 

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fat daddies

I'm a running 245 60 r15 on Rally II (15x7, if memory serves) rims. I forgot what the backspacing is, but think it's 4 1/2". No rubbing issues. (Although at first, the front rubbed slightly on the inner fender, but was able to adjust it via the bolt adjustment)... I personally like the same size tires all the way around, but that's just me. :) I gave up a hair on the tallness factor, so I could go with slightly wider tires, although I do like the looks of a filled wheel well. I don't believe I could've gone taller and kept the same width, though.
 

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yes i forgot to say they were 60 series on mine. I got the rims used so i have 3.5" backspace, Like G says if you like same width 245 or 235/60 R's all the way around and you can go with 3.5 - 4" backspace.
 

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Tireage

Only thing though, I am still running drums all the way around, and am not sure about about fitment issues with disk, and what that 3/8" extra per side with the different axle is going to bring to the table. As it is on mine, there seems to be a ton of room in the rear, now, though. Like instg8ter, and Alky says, I think the correct backspacing and wheelright is going to get you there.
 

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I also have a 68-69 chevy 12 bolt in my 67 lemans. Im putting an 18" 275 tire on the rear and need a custom backspacing to do it. The greatest bs most cast wheels have like boss 338 and riddler 495 are 5.5". Because the 12 bolt is longer and i want to put a 18" 275 tire on the back i need between 6-6 1/4" bs. Im going with billet specialties dagger wheels. You can get them with a 3.5-6.5 backspacing custom made to fit. I curently have a 275/60/15 drag radial on a weld prostar on the car now and just fits. If anyone has a similar set up with 17"-18" wheels on their car please share.
 

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i have Billet Spec wheels and love them, highest quality, mine are 15's. I am sure if E's around he can tell you what size as he has done all the measurements and is running Billets too. Anything 15" and up will be good with GM disk brakes.

 
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