As someone who has owned both G-bodies (79-80 Malibus) and F-bodies (89 GTA parts for the 80) there is little other than springs, front sway bar and steering box that directly swap over.

The G-body frame is tucked up into the rocker areas and longer. In order to drop your F-body over it you'll need to cut the front and rear subframes and most of the inner fenderwalls out of the F-body. While your at it, might as well and gut the floor from the firewall back to the taillights. Then you'll need to fab mounts to bolt the F-body body shell to the shortened G-body frame. Then fab up a complete floor pan, seat mounts, belt mounts, etc.

Then, bolt in a 9" Ford rear since the G-body rear (not GN) is 7.5" and weak.

If your up for it.. there is a basic nut shell of what will need done.

Or... a good set of subframe connectors, and a cage, (which you'll need either way since a G-body twists like a pretzel), a 12 bolt or 9" rear and fly.. for a lot less $$ and time. Bob

 

well for one i sorta desided not to go with the idea which you would know if you read my last post on this topic. and another thing i wouldnt need to cut the floor the stock floor would would there are ways of making things work with out getting to drastic lol. and the 68-72 pontiac lemans 12bolt rear bolts dirctly to a 80s gbody like it was ment for it.

 

Dude look at stock cars being built right now. None of them come close to 600 horsepower. Look at the vette they're making 400 horses. Maybe with some addons a little more. Thats probably as fast as a STOCK car is going to go. If you want to talk stock like a Ford GT look at the frame and suspension design on that thing. Not similar at all to an F-Body. A 600 goal stock car is unreasonable in any world!

 

Sorry, got lazy..

And no a 68-72 rear will not bolt directly in. The angles are different, and while it may bolt in with effort, the suspension will bind. Trust me on this.. I spent 6 years fiddling with the 80, starting with a complete frame off, including fabbing my own 9" rear with SVO discs and mini tubbing/frame notching it. Then theres the whole twin supercharger setup.. but thats a different thread.

 

The only worthwhile swap that I know of is the 8.5" used in the GN's and I think some of the olds (442) from the 80's

 

Obviously the G-Body swap was shot down, but most of you are comparing the full frame swap to race environment cars, which I can understand due to the fact that he listed a 600hp car or some such.

What kind of impact though would a full frame have in an accident vs. a unibody with subframe connectors? My camaro had been in an accident unbeknownst to me when I bought it (before carfax got popular ) The whole car was twisted, and I didn't find out until 2 yrs later when I changed out the weatherstripping for the t-tops and found out that someone had turned the t-top brackets sideways to make everything work.

Ever since then, I can't help but hate unibody construction and have wondered about the benefits of a full frame holding up better than subframes.

What do you guys think?

Mathius

 

I've heard, don't take this as gospel however, that full frame cars are worse off than unibody cars in light collisions. FWIW.

 

Its entirely up to the design. There are week versions of both. Ignoring that, since you’re comparing a large 3 dimensional part vs what is basically a flat part, the unibody has potential to be more rigid for a similar size/weight. OTOH, if you try to run your f-body into a full size truck, well, you can guess who would win

 

I hate to bust anyone's bubble here, but the F body torque arm rear suspension really isn't that good for drag racing. You'll get to a point where it will be impossible to keep the front end on the ground. You all think standing a car up on the back bumper is a good thing? The torque arm is too long and on the wrong side.

 

I think you've missed the point of the conversation.

 

hehe, tell Jim Filipowski that. just went 7.91@183 on BFG dr's with stock style suspension and the front barely came off the ground.

 

to get the absolute best launch the suspensions instant center has to be in the same place as the car's instant center. The torque arm places the suspension instant center way too far forward which tries to make the body roll back and lift the front wheels off the ground. With a torque arm you have to cripple the rear suspension with high rate shocks and springs to the point where it reacts almost like a solid mounted rear.

About the thread in general- What he wants to do will give him a more durable car for not a lot of money, but it will be a lot of work.

 

¿Que?

Add antisquat by chainging either the LCA or TA geometry slightly and the rising back end will cause the front end to have much less of a tendancy to lift. Past that a lot can be done with springs, struts/shocks…

On the wrong side??? For what?



As far as I can tell you’re confusing 2 different things that you’ve read someplace (and actually I think that I know where you’ve read them, but that’s not really the issue). Yes, some aftermarket rear suspension parts do in the long run end up limiting the motion of the rear axle to the point that it is almost bound up, but that is in no means necessary to make it work.

What is “the car’s instant center? If you mean CG (which is not an instant center, but it is another imaginary point), well, you can manipulate it and the rear suspension’s IC to change how the car reacts, but in no way do they have to be the same point for the rear suspension to work.

 

my bad- yes, it's the car's genter of gravity, not instant center. How do you figure out the suspensions instant center on one of our cars?

The torque arm is on the wrong side, it should be more to the right. If you get it in the right spot you won't need an airbag in the spring and/or preload on the swaybar. Driveline torque likes to unload the right rear wheel, the torque arm wants load both rear wheels. Move it to the right and it will put more of a load on the right wheel.

 

I agree with the others that you don't need a frame swap for numbers like these. That said...

If you have the skills to try a frame swap (I have seen very few good ones on ANY car), why not buy some rails from Morrison or Alston or somebody like that (they'll sell you mandrel bent rails that actually are made for your car, put in some crossmembers, and go with the suspension of your choice (there are tons of possiblilities), instead of going with a weak, crack prone chassis that you're going to have to strengthen and replace nearly everything to have something decent? Even if you manage to get a G-body chassis or some other under the car, its unlikely that you'll have the result you want.

BTW if you're staying away from a cage for stealth reasons, don't you think the sound of a 600hp engine is going to give it away anyway (if the stance doesn't)?

 

Even still, I have seen 3rdgens with tons of HP (maybe not 600, but that is a very high number and I doubt it would make that much) with just suspension mods. There is NO need for a frame! Subframes, yes. But just take all that $$ and do something better with it!

 

exactly what i am saying. you can get these cars into the LOW 11's high 10's without a cage. actually, with all the aftermarket suspension available, you can do it with just suspension and sub-frame connectors. it's not legal, but totally possible.