Body twist

[85_455_cutty]

I have an 85 cutlass that im putting a built up 455in and people have been telling me im wasting my time with the car cause as soon as it launches good once the frame will twist and it will be done. Is this true or do I need to start looking into ways to really strengthen my frame up good?

 

[shotgun]

If you start to hook, then yes it needs to be braced up.

GM made plenty of stuff to beef these cars. Aftermarket has some goodies also.

Start with Poly Body Bushings and go from there.

Read this.

http://gbodyforum.com/viewtopic.php?t=8 ... highlight=

 

[dogsht]

Great job on the diagrams shotgun! I missed that post.
85 455 Cutty, The criss cross brace across the back of the trunk ie behind the rear seat is probably one of the most important to save your body if you build something that really launches hard. Without it the A pillars in front top corners of the opera windows will crack. First and most noticeable damage.

 

[85 Cutlass Brougham]

The Opera window crack problem is due in large part to how GM attached the roof at the joint in this spot. It is only tack welded in one small spot in the middle of the B pillar with NO support at the corners of the window opening or the door window opening. When I did my bodywork ( my car had a vinyl top originally), I welded this seam up fully, and also added a brace made of sheet metal to hold the roof to the B pillar better in the door window opening. My car is not a drag car, but rather a handling car so the forces are not as severe as they would be under a hard launch. Even still, the filler I had put in when I first took out the top cracked in these corners, so I fixed it better this time.

Oh, and Shotgun, I stickied your previous post. Thanks for the information and I plan to use as much of it as I can. So far, I only have the GP brace and poly bushings done, but I hope to add the rest of the stuff in the future.

 

[shotgun]

"Oh, and Shotgun, I stickied your previous post." EEwwww. :lol:

 

[85_455_cutty]

Thanks for all the advice guys. How much does boxing the frame usually cost? Im gonna have pics of my car up soon ive been workin all my days off on it gettin the engine in and tryin to get my drive shaft shortened to fit with a th400. Its been almost 2 years since my car has moved under its own power but its almost ready to drive again.

 

[pontiacgp]

I would be checking the factory welds on the frame for bad welds and weld the seams that are not yet welded.....you won't have to look hard to find some of the crap welding on those frames....then box the frame and depending on the hp and torque you might also want to either x or k the frame to stiffen it up...it's a full frame car so the body is not going to twist if the frame doesn't...we ran a G body for years and the body we ran was a five star sheet metal with the only body bracing was to hold it in place....the body won't stop the frame from twisting no matter how many braces you want to install

 

[85 Cutlass Brougham]

C'mon now, Pontiacgp, are you saying that GM's union factory workers were anything but the most fastidious, quality conscious people when it came to assembling cars? :lol:

 

[pontiacgp]

C'mon now, Pontiacgp, are you saying that GM's union factory workers were anything but the most fastidious, quality conscious people when it came to assembling cars? :lol:

actually the frames were all build by outside production....GM's quality control was somewhat lacking those days but I'm sure kickbacks were alive and well.......I had a few friends who worked at Oshawa in years gone by and some of the stories make you wonder if any of their cars were safe....lol.

we have one factory in my town that built frames for GM for years but they just closed up. There's a rumor that there are a bunch of G body frames just sitting in storage there doing nothing..

 

[85_455_cutty]

So is this all stuff im gonna have to take the body off the frame for?