New 1979 C15 owner, Need advice on drop and wheel backspace

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peargrower

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Hi Guys, I just acquired a 1979 GMC C15 that I am going to start to dump $$$ into. Im thinking by pics I seen that I want about a 4/6 drop and 17" or 18" wheels. I need help with backspace size and tire size. This is basically a open slate, I am just starting and have made up my mind that I will be putting either a LS2 or an LT1 in it. It will be a ground up resto. Any help on tire size and backspace would be greatly appreciated. Also, include pics if you can, I like to see what everyone has. Thanks
 

Vbb199

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Well ill share with you just now today I learned , I should be able to easily clear 12.5" wide slicks on the back of my stock width 12 bolt in my 79' c10.

I heard the best you could do without tubbing it out is 11.5, but with Nascar wheels, you can apparently clear 12.5 wide. Perhaps even 13
 

Bennyt

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AMD sells a widened bed floor and tubs so you can narrow the axle and go all the way to the frame rails pretty easily.
 

peargrower

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Im not looking to tub it, however the wider the better as long as they clear in the back
 

Corvette Ed

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Sounds like a plan. Welcome aboard.
 

Vbb199

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350, 502
Well ill share with you just now today I learned , I should be able to easily clear 12.5" wide slicks on the back of my stock width 12 bolt in my 79' c10.

I heard the best you could do without tubbing it out is 11.5, but with Nascar wheels, you can apparently clear 12.5 wide. Perhaps even 13


As it turns out, 12.5 wides will clear, but when I probably go lower than 4" drop it'll require taller tubs
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