> If you're not running a lot of horsepower, consider a 7.5" rear from a full-
> size GM. Mine is from an 84 Pontiac Parisienne, and it was a straightforward
> installation. The main drawback is that stock-offset wheels rub slightly on
> the inside (the tires do, not the wheels). To center my 8" wheels in the
> wells, I'm running 3.75" backspacing with VERY slight rubbing, but I think a
> narrower wheel with 3" backspacing would be perfect. My rear isn't lowered,
> but I think I'd have to make some kind of modifications if I wanted to lower
> it.
> I also have a 78 Pontiac Bonneville 8.5" rear available, and it is enough
> wider to possibly fit with stock wheels. Drawback here is mainly the 5" bolt
> circle as opposed to 4.75" (I'm running Camaro discs on the front).
> Gear ratio will tend to be ridiculous with these rears, 2.73 in the 84 and
> 2.56 in the 78, but it may be worth trying. My 48 can run 75mph all day long
> with these gears, but long up-slopes have it struggling for breath. Shifting
> down manually to second gear allows it to maintain speed while still not over-
> revving (or even exceeding 4000 rpm). That's with a 350TH, not a 4-spd manual.
> Hope this helps.
>
> Mike Jensen
> 48 1/2 ton
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
I have a '77 Pontiac Paresienne Brougham rear with 3:08 gears in my '48.
I had the same problem with the stock rim offset. My new wheels are
15x7, with a 3.8 inch offset, with 215/75/15 tires. They do not rub at
all any more. I do have the problem of 5 inch bolt pattern on the back
with 4 3/4 rotors on the front. :-( I just carry a mini spare with both
bolt patterns. The 3:08 gears allow me plenty of snap off the line, and
a nice rpm level for highway driving.
Alan Gingles
1948 Chevy "1314"
http://www.nucleus.com/~agingles
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