Hey fellas Ive been pretty quite for a while as Ive had life and few things get in the way of my build. I have a question for the Pontiac guys that have done a V8 swap on their 53-54s and I guess 49-50s are pretty similar too. My question is what rear end are you running? Ive had people tell me 2nd Gen Camaro, Ive heard 1957 Pontiac is the way to go, Ive even had 90's Chevy S10.. Now money is somewhat an issue so Id like to find the easiest route that will work with the 400 under the hood! I do have a 1957 Pontiac and 1971 Camaro Rears available to me so I'm wondering if I should jump on either one of those.. any input from you fellas will be appreciated, Thanks in advance.. ESP
I'm not sure there is any good reason to change the rear end from the original, unless the gear ratio is way too low (high numeric). In which case, I would recommend you determine the ratio in the '57 Pontiac axle. If the ratio is a sufficient improvement over stock, then it would be a good choice for a couple of reasons. One, it matches the wheel bolt pattern of your present setup.......second, the Pontiac axle has replaceable self-contained axle bearings and the Camaro uses a different bolt pattern and the axle shaft itself as the inner race of the bearing. It works, obviously, but is not as durable and is more expensive to repair if the bearing fails. The '57 Pontiac rear end is stronger than the Camaro......'57 thru '64 Pontiac and Olds rear ends were the 'hot tip' for a long time in drag cars because they were so rugged.
Thanks Hnstray, see I'm horrible when it comes to gear ratios and such and I'm not afraid to admit it.. From what I understand the gear ratio on the 57 is the same as my 53 but like you mentioned as well as a few others the 57 was stronger... Ive been told that 2nd gen Camaro will pretty much drop right in and would be better suited for the 400.. believe it or not the bolt pattern is what makes me hesitate...
you can get gears for the 57 , I have a 8.5 out of a camaro in mine but my front was clipped with a camaro subframe so my bolt pattern matches , stay away from the s-10 rears unless its a 8.5 the 7.5 is a real weak rear and if it sees the 400 it will break from the thought of having to deal with that much torque .. Imo I would use the 57 as my freind is running one in his 62 chevy II behind a fuel injected and blown 496 , and it ( the rear ) was out of a old gasser that burned 30% they are a stout unit ... and Pontiac like the lower gear numbers , a 3:73 and up is basically useless for one .
Unless you're going to drag race the car, I'd use the original rear. A 3.23 or even a 3.08 [good all-around gearing for a street car] should be in your housing if your 53 is an automatic car. If not, it's easy to change out the gears if you find you don't like the 53 gears. The original rear gears are strong enough to use behind a mild 400. I've used these rear axles under both my 48 and my 41 Pontiac along with a slew of 55-56 Pontiacs and never broke anything BUT! I did bust a left rear axle shaft in my 57 Pontiac with a 389/4 speed. Go figure.
I put a Camaro 10 bolt under the 53 I built and had to have Wheel Kid build me some custom offset inward rims so I could put the skirts back on, the axle was a touch too wide. Don't know if you plan on skirts but just food for thought if you do.
Rocky and Stimpy, thanks fellas you both answered my question beautifully. I was hoping to hear something like that, I knew my Pontiac is a 3.08 I just wasn't sure if it was good enough.. Not planning on racing but I also don't want it to drag on the highway...
the 3.08 gear is a good gear for a later Poncho , its funny but it was almost the middle of the road gear ratio in the 70's for them , it allows you to use the torque they make thru most of the power band . it will move the car very well considering the Trans hams had that ratio in it and was pulling almost 4000 pounds with it
Stimpy, again man, thank you so much for your information. This is my first Pontiac and my first project of this magnitude, everyone told me "buy a chevy" its an easier build..lol.. but I fell in love with my 53.. I might still purchase the 57 rear just in case, but you and Rocky telling me that Ill be fine with what I have has relieved major stress..
If you can buy the 57 rear end for a decent price, great! They're wonderful trading material but damn! That's a lotta unsprung weight to be bouncing around under a 3300-3400 lb car. I'll bet the 56 and earlier axle is prolly 50 LBS lighter and the 57 axle is not really necessary for a street driven poncho with a 400/automatic in it. The 3.08 gears will be perfect for a 400 with a stock or mild cam and a non-overdrive tranny. Plenty of power off the line and a pleasant RPM for hiway driving.
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