My 78’ Pontiac GP/SJ 454 build

[78BB-Pontiac]

I have used 2 different headers both from Hooker. The cheapest was the 2455 full length designed for 68-72 A-body cars like the Chevelle. Took some massaging to fit but for $100 or so I was happy. I believe I had to grind out some of the lower control arm mount and move the brake proporting valve back on the frame a few inches. The latter probably isnt NEEDED but I don't like the idea of hot brake fluid.

My current headers are the Hooker slip tube 2241 headers made specifically for BBC swaps in G-bodies. These are much more expensive but they are "tuned" and fit better. The only reason I made the switch was because I found them dirt cheap out of the blue locally. Only downside besides the price is dealing with the slip tubes leaking. Will need high temp silicone while assembling them.

Both headers, if not ALL headers will need some relief ground out on the bottom of the mounting flange when using bigger head bolts like ARP. Both headers mentioned are full length, 2" primary into 3.5" collectors.

Well considering I have a long way to go on this car I think I’ll check out those 2455 hookers. The car has stock manifolds with two small pipes going back on both sides of drive shaft to two flomasters just before the rear differential. It’s kinda loud and would really like it out the back using the mandrel bent 2-1/2 kit I have.
Thanks for the info, I really appreciate it!

 

[GuysMonteSS]

Find a header in the 1 3/4" to 1 7/8" range and it will be more than enough to feed up to a 600 hp big block.

What he said !!
Guy

 

[454GrandPrix]

I'm three weeks late seeing this, but I don't visit this forum every day. Sorry 'bout that.

What do you think about a Ford 8.8 rear end from a 88’ fox body mustang for my Pontiac? The guy wants $150 for it. I know it will need different axles. I’ll just take the hole thing in and have it rebuilt and set up for my car.

That is exactly what I have in my '80 GP. I used the Trick Chassis correction kit with their upper spherical arms, plus TC adjustable lower arms. I cut off the Ford coil spring perches and welded aftermarket ones onto the tubes to fit the G-body layout, but other than that the axle housing is untouched. The upper arms are bolted to the stock Ford mounting points, the lower arms are bolted to the stock Ford mounting points, and the shocks are bolted to the stock Ford mounting points. My axle sits properly under the car, and it rides and performs well. I think the Fox 8.8 is a fabulous low-buck axle option for us G-bodies.

Later, I decided to eliminate the c-clips (and simultaneously upgrade to stronger axle shafts). I bought a Strange axle package which included their eliminator kit. Installation required me to hacksaw off the outer ends of the tubes, but otherwise it all bolted together nicely. While doing the axle swap, I also installed a Detroit TrueTrac helical limited slip, which is awesome and probably one of the best mods I've made to the car--I would highly recommend it to anyone.

$.02

 

[78BB-Pontiac]

I'm three weeks late seeing this, but I don't visit this forum every day. Sorry 'bout that.



That is exactly what I have in my '80 GP. I used the Trick Chassis correction kit with their upper spherical arms, plus TC adjustable lower arms. I cut off the Ford coil spring perches and welded aftermarket ones onto the tubes to fit the G-body layout, but other than that the axle housing is untouched. The upper arms are bolted to the stock Ford mounting points, the lower arms are bolted to the stock Ford mounting points, and the shocks are bolted to the stock Ford mounting points. My axle sits properly under the car, and it rides and performs well. I think the Fox 8.8 is a fabulous low-buck axle option for us G-bodies.

Later, I decided to eliminate the c-clips (and simultaneously upgrade to stronger axle shafts). I bought a Strange axle package which included their eliminator kit. Installation required me to hacksaw off the outer ends of the tubes, but otherwise it all bolted together nicely. While doing the axle swap, I also installed a Detroit TrueTrac helical limited slip, which is awesome and probably one of the best mods I've made to the car--I would highly recommend it to anyone.

$.02

I recently found a problem in back of my car. Someone must have bottomed that car hard on the drivers side rear. The mount that the coil spring sits in and shock bolts too is pushed up I would say at least a inch compared too the other on passenger side.
Thinking I might need someone with a frame rack, heat it up and bend it back down a little.
Makes the car sit low in back on drivers side about a half to 3/4 or a inch. Any suggestions? I have a couple little blocks in that spring for now

 

[Wraith]

Pics? It would take a lot to move that area that much

 

[78BB-Pontiac]

Pics? It would take a lot to move that area that much

That bracket doesn’t have to be bent back down to much, a inch or so..

 

[fleming442]

You sure the body mounts aren't just collapsed on that side?

 

[Wraith]

You sure the body mounts aren't just collapsed on that side?

I agree.

 

[78BB-Pontiac]

I agree.

Lol.. No that car is clean as hell, no rust anywhere.

 

[78BB-Pontiac]

You sure the body mounts aren't just collapsed on that side?

Nope! That car is very clean. There is no rust and the rubber is good. If you look at that bracket, it’s bent up towards the floor of trunk. Someone bottomed that car hard it looks like to me. I don’t see anything structural different but that spring and shock mount being pushed up about a inch or so higher that the other side.