Frame differences among years

[slowboi]

Did a search for this but came up short. I am doing a restoration on an 86 Grand National and I have a fairly clean '82 frame in my possesion that would be a good starting point. My question is:

Are there any differences between an '82 frame and an 86 frame?

 

[Turbotre]

There is an extra piece added for the transmission crossmember to the newer frames with the 200-4R transmission.The 200-4R was not officially available in the G-body until 1983.
Your 1982 frame will be missing this piece.

 

[slowboi]

bummer, i will have to get it up on a hoist and check it out

 

[charlief1]

You can get the pad as an add on from summit and jegs I believe or you can do like I did and make it.

 

[slowboi]

You can get the pad as an add on from summit and jegs I believe or you can do like I did and make it.

So its not worth me trashing this frame and looking for another one..... I guess it should be pretty simple to add the cradle?

 

[slowboi]

would this be the part I need to keep this frame?

http://www.summitracing.com/parts/SUM-770307/

 

[slowboi]

This is also available: frame extender kit and a double hump crossmember.....
http://www.transmissioncenter.net/gforce_double_hump_crossmembers_.htm#th400

[QUOTE]#32XM. Same as above but with frame extension kit for 1978 - 1983 cars with a 400 or 200-4R transmissions. Cost $259.00[/QUOTE]

 

[novaderrik]

might as well make sure the new frame is straight and square and box it up to make it stiffer..

regarding the extra tab for the overdrive trans- it would be a simple matter to add the necessary mounting pad by just cutting it off the 86 frame and welding it to the 82 frame in the same place, or just making a copy of it and adding it.

 

[charlief1]

The second link has both the extension and the crossmember as a package for $259 or you can take the one off the stock frame and weld it on or make a new one that's heavier. I do agree 100% with Derrik though. Box the frame and it will help the car over all since the stock one is a noodle in the middle.

 

[slowboi]

regarding the extra tab for the overdrive trans- it would be a simple matter to add the necessary mounting pad by just cutting it off the 86 frame and welding it to the 82 frame in the same place, or just making a copy of it and adding it.

I thought of that, however I got this frame for free and my motivation for using it is I can build the car gradually and move pieces over without disassembling the 86 completely as I don’t have a ton of room to do this.

The second link has both the extension and the cross member as a package for $259

My plan was to mod the frame for stiffness and to notch the rear for bigger tires. I will be boxing the frame for sure.
So the extension piece and cross member are the only parts that are different about the frames? The G-force part looks pretty stout, I may buy the extender and cross member and weld them in rather than bolt them for increased rigidity.

 

[charlief1]

My plan was to mod the frame for stiffness and to notch the rear for bigger tires. I will be boxing the frame for sure.
So the extension piece and cross member are the only parts that are different about the frames? The G-force part looks pretty stout, I may buy the extender and cross member and weld them in rather than bolt them for increased rigidity.

I can tell you personally that mine was a 3 speed frame and boxing it was one of the smartest things I've done before adding the 4 speed mount. Do not use thicker than 1/8 thick steel though for the boxing. I'd honestly do the boxing first and make the bracket needed and either get the G force crossmember or one off a 4 speed car. I cut my front crossmember out and lowered it 3/8" to get rid of the crash/crumple zone at the top as well as lower the engine some for a better CG. Since I've got a few more tricks up my sleeve I will be making the crossmember for the tranny myself to play with some other things I that have to do with the CG as well.

 

[turbodave231]

The frame also has a partial VIN stamped on the outside driver side frame rail. You can't see it until the body is lifted off the frame. I had an 86 that was hit real hard in the front. I replaced the frame with an 85 frame. I later sold the car and disclosed the repair/replacement to the new owner. If originality is important, and you are really good with a welder, you could cut this section out of the old frame and weld it into the replacement frame and then metal finish it.

 

[slowboi]

The frame also has a partial VIN stamped on the outside driver side frame rail.

Im not too concerned about originality but thats good to know! Could that vin be used to find out what year the frame is? I was told the year but it was a bare frame when I got it.... I guess it would be nice to know.

 

[charlief1]

Look on the inside of the right rear rail. The DOM is stamped near the bumper support.