[gtonut1]

I am building a '63 into a gasser type car and need info on how to install a '57 Pontiac rear end to replace the transaxle. I want to use the existing body to rear end mounts if possible or use leafs. It will have a straight axle up front. Main use is for the street with some 1/8 mile passes.
Thanks, Butch

[tom s]

Do a search on the tech forum,,tons of info.Tom

[gtonut1]

Thanks

[c5farmer]

Check out the pictures in this post. http://forums.maxperformanceinc.com/...t=leaf+springs

I think leaf springs are the way to go on a "gasser" build. Post pics as you go.

[Doug]

If you want to use the "original" mounting points with a leaf spring you can use a later model (year?) Mopar axle setup and have someone make up a leaf spring setup that has a very short front section (around 19" or so long). The front eye on the leaf can be made to fit the original (control arm) mount point with a little work. The big drawback is that the Mopar axle's spring perches are so wide apart that the inside of the tire is very close to the spring and there is not much room from the outside of the tire to the bead on the wheelwell. An advantage to the Mopar axle is that it has the same lug bolt pattern (4 1/2") as the Tempest does. Another advantage is that the 57 Pontiac does not have posi rearend parts whereas the Mopars have posi units.

I have a parts car that had one of these Mopar rearend setups with the "custom" leaf spring setup. The guy I bought the car from ran the setup with a 455 turbo 400 setup for awhile and the problem he had was the differential hitting the floorboard under heavy accelerating. He didn't have one of those Mopar snubber block setups on it. He had the "custom" leaf spring made up by his blacksmith uncle who shortened the spring and rolled a new eye on it. He had a 3.08 or so ratio posi unit in it.

There are several Ford and Mopar rearends that have nearly the same overall width as the 57 Pontiac. I think that maybe the early Roadrunners/GTX type cars had a rear with spring perch spacings the same as the 57 Pontiac. Same thing for some early Mustangs too as I recall.

Bottom line is that you can make up housings with perch spacings as you wish so that isn't a big deal. I would however point out again that most of the Ford and Mopar rears have the lug bolt pattern interchangeability with the Tempests.

You can see some pics of a leaf spring setup I am building in the thread listed above by c5farmer.

[tom s]

use a 57-58 housing and a 31 spline center section.Fabcraft has all the parts to build a good posi now.I have done 3 of them and have found coil overs and ladder bars by far the easyest to do.If you want you can always have axles redrilled for the 4 1/2 pattern.Wilwood makes a rear disc setup for the pontiac rear and Scarebird makes both front and rear I believe.I think your trying to do the gasser look but there is nothing wrong with a good 63 front suspension.Tom

[Doug]

Originally Posted by tom s

use a 57-58 housing and a 31 spline center section.Fabcraft has all the parts to build a good posi now.I have done 3 of them and have found coil overs and ladder bars by far the easyest to do.If you want you can always have axles redrilled for the 4 1/2 pattern.Wilwood makes a rear disc setup for the pontiac rear and Scarebird makes both front and rear I believe.I think your trying to do the gasser look but there is nothing wrong with a good 63 front suspension.Tom

Tom, What axles did you use in the 57-58 housing with the 31 spline carrier?

[tom s]

Moser,was not a issue at all.Tom

[gtonut1]

I have some springs from a '74 Ventura and I think I will have them shortened 3" and use them. The spring rate should be good and not to stiff. Since I am using GM A body front disc setup I will use the 4.75 bolt pattern in the rear also. I tried putting ford wheels on the front but the center hole is too small compared to the Pontiac original wheels. My front suspension is in good condition but I have always wanted a straight axle Tempest since i saw one at Fremont Raceway when I was racing my '65 GTO in the later 60's.
Thanks to all for your help, I WILL get this done.