The Jalopy Journal

Tinbender · 06-06-2006, 07:27 PM

One of our new guys "Heavy" was asking about a GM "G" body frame swap for his 50 chevy P/U. I'm in the process of doing one for my 46 Stude P/U so I thought I 'd post some pictures in case any one else was thinking about this swap.

I don't seem to be able to locate the first pictures of the chassis, but it's what is known as a perimeter frame. That means it kicks out right behind the front suspension and the rails run along the rockers, then kick back in right before the rear suspension. This is the biggest problem with this frame. It's too wide thru the center section for a lot of cars, and most pick ups.
G bodys were the mid sized GM cars from 78 up. Malibu, Monte, ect. Some of the higher performace cars come with some good handleing packages. Mine was just a lowly malibu 4 door, which will be just fine for this daily dirver.

It's a short arm / long arm front suspension just like the S-10. Some of you my know better than me, but I'm pretty sure most of the parts interchange with the S-10. In my opinion it's one of the best all around designs out there. The rear suspension is a 4 link design, also an excelent choice. The track is 57&1/2" making it perfect for my Stude.

This chassis will replace the stock Stude chassis that I had subbed with a 77 Nova. The sub worked great, but I eventully channeled the P/U and had to run some small tires that I never did like due to the 60&1/2" track of the Nova. I also had the stock parallel leaf suspension with the nova rear mounted on top of the springs. Even with a few leaves removed, it still road a little harsh in the rear.

In my case the wheel base was 4" shorter than my stude. 108 &1/2 if memory serves. That was perfect, as I always thought my rear fenders needed to move forword a bit to ballance out the look of the bed.

If you need to change the wheel base for your application I'd suggest you do it first. Before you remove them. This will make it easier to jig the chassis up for the new rails. Cut the stock rails in the middle and use some rec tube, or angle iron to hold the rails in alignment and weld them back together.

The most important measurements at this point are length, of course and dimond or X check. Find points at the front and rear on each rail that are the same side to side, and measure diagonally. The measurements should be the same.

As for level, I haven't found any thing that workes better than large bubble levels. One on the front and one on the rear will help you keep any twist out of the chassis.

Once you have the length where you want it, It's time to replace the center rails. I have access to a frame bench, but you don't need one. You just need to stablize the front and rear clips. You can weld tubing in an X across the center, or make some wide U shaped tubes and temperarlly weld them to the front and rear clips. I've seen this done under, or over the frame. It doesn't matter as long as they are put in before you remove the rails, are out of the way of the new rails, and keep both ends from moveing.

We mounted this frame on a car-o-liner bench, and all of the fab work was done by one of my female students. This was the first time she had fabricated ANYTHING! She was one of my best welders in this last group, and she gained tons of confidence from this project! At the start I think she thought I was nuts to let her do this. Buy the time she was done she couldn't belive how easy it was.

I think I'd better post a picture now. I'm tired of typing. Both of my typing fingers are getting tired

These first two pictures are the chassis on the bench with the new rails set in place. The rails are made of 2"X3" 1/8" wall rec tube. They are inserted into the orig rails. The kick up at the front put the rails right about the same hight as the orig.

Slag Kustom · 06-06-2006, 07:41 PM

great use of the car oliner i have done the same thing but used 2 sets of arm to hold the front and rear sections so i could ajust the legnth and then used the caroliner meauring system to make sure it was perfect befor welding the new rails in.

Tinbender · 06-06-2006, 07:45 PM

These next pictures show the new rails installed. DONT MIND THE RUST! We ran out of room, so it got shoved out in the rain. The frame will get sand blasted & painted before I set the body back on. At the front the orig. rail was stager cut, and the new rait was set inside the orig rail. It was plug welded thru the outside of the orig rail, seam welded then 1/8" plate was cut and formed to close off the two sections. The one mistake that was made was in the kick up. Cheri got ahead of herself and welded the kick up without sleeveing the inside. (I had 19 other students, can't watch em all, all the time!) Not a big deal, but I like over kill, so I'll be gusseting, or fish plateing that joint later.

In the rear the new rail was kicked out and that joint was sleeved on the long sides(sort of an internal gusset) You can see the plug welds that go into the inside gusset plates. Also the joint was set up with gaps so that the weld penitrates the internal plates.

Tinbender · 06-06-2006, 07:48 PM

Not sure what happened to the pics Hang on I gotta resize!

Tinbender · 06-06-2006, 07:58 PM

Quote:

Originally Posted by Tinbender

Not sure what happened to the pics Hang on I gotta resize!

OK, that was a pain in the ass!

Tinbender · 06-06-2006, 08:09 PM

Yeah, the car-o-liner is great. When she cut out the rails it didn't move a bit! Still have some work to do. The frame will get a X member at the back of the cab, and a trans X member. And of course a new rear section to mount the bed. I have 100 bucks in steel, and 25 in gas and wire. Paid 350 for the car. My daughter drove it almost two years.

I know some of you out there don't like clips, or frame swaps. That's fine. Do what ever you want. For a lot of us, and a lot of cars they are a very viable swap. When I first clipped this truck I bought a running driveing nova for 75.00 I had her on the road for less than 2 grand. I drove it for 5 years and had to replace the idler arm, and front pads. Spent less than 50 bucks!

As for this swap, I had the malibu. It ran and drove and road great. Got it back when my daughter bought a honda! I always thought ,man if my Stude only drove like this. Now it will!

Hackerbilt · 06-07-2006, 08:43 PM

Excellent and interesting!
BttT where this kinda tech should be.

Cheri rocks!
She's off to a great start by the look of her work on this build.

**wayfarer** · 06-07-2006, 09:52 PM

Looks good Eric. I was wondering if you still had the bulletnose, but I see it in one of the pictures.

crash 51 · 06-07-2006, 10:16 PM

Tinbender. Awesome Info. I Was Set To Clip A 50 Chev Pu Next Week. I Found A 84 Monte For $400 That I May Just Put The Whole Frame Under The Truck. Can You Send Your Students To Texas On A Feild Trip For About Two Weeks?

Turbo442 · 06-07-2006, 10:25 PM

This is a really cool post. I like the different approach you took with narrowing the rails so it woud work.
I have an 84 Cutlass with a Grand National driveline, it has the same chassis.
The G-bodies have a ton of factory parts to make them handle and a large aftermarket following. You can get lowering springs, dropped spindles (S-10 spindle is the same), upgrade to larger 12" rotors and larger sway bars. If yours didn't have a rear sway get a $10 one at the junk yard and bolt it on, the holes are already drilled in the lower arms. Speaking of control arms, the rears can be "boxed", just weld a flat piece of steel, or you can buy tubular ones. This will help with handling as well as acceleration. It really does make a difference in the handling as without they feel kinda loosey goosey.
I put an IROC Camaro steering box in mine for fast ratio steering. I have done all these upgrades to mine. It handles awesome and stops great as well.
Oh and in the rear another mod people like to make is to notch the rear frame rail where it goes over the axle. You just cut and replace the metal with thicker plate but you cut it back so you have a few inches left. I had mine done so I could fit some 315/35/17's which are about 13" wide tires on a 10" rim.
Anyway, hope I didn't hog your thread. I just wanted to say there is a lot of potential and options in this chassis. Oh, and the frames are already drilled for Buick, Chevy, Olds or Pontiac motors and all parts are readily available.

Tinbender · 06-07-2006, 10:32 PM

Actually I sold the the bullet nose to the refinish instructor. Hated to let it go but I have far too many projects. Dan, the new owner is one of the best fabricators I've ever known, so I can't wait to see what he does with it.

Crash51, they are out for the summer in a week. I dont care where they go, as long as they go!

They have been a good group, but I'm ready for summer, and a new group next fall.

Tinbender · 06-07-2006, 10:37 PM

Turbo442, thanks,good info. I'v got 15X10 slotted mags that fit nice for the back. I may do some of the upgrades you mentioned. This truck is just going to be a driver, but you know how it goes, it's hard to leave them alone!

Turbo442 · 06-07-2006, 11:53 PM

No problem.If you have any questions or want to know some more sources for info./parts let me know. Did you know S10 springs work well in the front? Stiffer and you can cut them to lower them. Camaro springs work well in the rear.

doctorj928 · 06-08-2006, 12:17 AM

hey eric its looking good i will have to stop by before you get out for the summer and check it out i havent been by in a while

jeff

heavy · 06-09-2006, 11:57 AM

Big help tinbender thanks!

don meyer · 01-10-2007, 04:10 PM

I welded the G-body front clip(cut about 1 to 1 1/2" behind the lower A-arm) to the Chevy trk AD frame. Works like a dream. I also used Moog lowering springs & Camaro iroc-z box.

06-06-2006, 07:27 PM	#1
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	G body frame swap pics for Heavy. One of our new guys "Heavy" was asking about a GM "G" body frame swap for his 50 chevy P/U. I'm in the process of doing one for my 46 Stude P/U so I thought I 'd post some pictures in case any one else was thinking about this swap. I don't seem to be able to locate the first pictures of the chassis, but it's what is known as a perimeter frame. That means it kicks out right behind the front suspension and the rails run along the rockers, then kick back in right before the rear suspension. This is the biggest problem with this frame. It's too wide thru the center section for a lot of cars, and most pick ups. G bodys were the mid sized GM cars from 78 up. Malibu, Monte, ect. Some of the higher performace cars come with some good handleing packages. Mine was just a lowly malibu 4 door, which will be just fine for this daily dirver. It's a short arm / long arm front suspension just like the S-10. Some of you my know better than me, but I'm pretty sure most of the parts interchange with the S-10. In my opinion it's one of the best all around designs out there. The rear suspension is a 4 link design, also an excelent choice. The track is 57&1/2" making it perfect for my Stude. This chassis will replace the stock Stude chassis that I had subbed with a 77 Nova. The sub worked great, but I eventully channeled the P/U and had to run some small tires that I never did like due to the 60&1/2" track of the Nova. I also had the stock parallel leaf suspension with the nova rear mounted on top of the springs. Even with a few leaves removed, it still road a little harsh in the rear. In my case the wheel base was 4" shorter than my stude. 108 &1/2 if memory serves. That was perfect, as I always thought my rear fenders needed to move forword a bit to ballance out the look of the bed. If you need to change the wheel base for your application I'd suggest you do it first. Before you remove them. This will make it easier to jig the chassis up for the new rails. Cut the stock rails in the middle and use some rec tube, or angle iron to hold the rails in alignment and weld them back together. The most important measurements at this point are length, of course and dimond or X check. Find points at the front and rear on each rail that are the same side to side, and measure diagonally. The measurements should be the same. As for level, I haven't found any thing that workes better than large bubble levels. One on the front and one on the rear will help you keep any twist out of the chassis. Once you have the length where you want it, It's time to replace the center rails. I have access to a frame bench, but you don't need one. You just need to stablize the front and rear clips. You can weld tubing in an X across the center, or make some wide U shaped tubes and temperarlly weld them to the front and rear clips. I've seen this done under, or over the frame. It doesn't matter as long as they are put in before you remove the rails, are out of the way of the new rails, and keep both ends from moveing. We mounted this frame on a car-o-liner bench, and all of the fab work was done by one of my female students. This was the first time she had fabricated ANYTHING! She was one of my best welders in this last group, and she gained tons of confidence from this project! At the start I think she thought I was nuts to let her do this. Buy the time she was done she couldn't belive how easy it was. I think I'd better post a picture now. I'm tired of typing. Both of my typing fingers are getting tired These first two pictures are the chassis on the bench with the new rails set in place. The rails are made of 2"X3" 1/8" wall rec tube. They are inserted into the orig rails. The kick up at the front put the rails right about the same hight as the orig. Attached Thumbnails __________________ I have never completely understood anything

06-06-2006, 07:41 PM	#2
Slag Kustom Old School HAMBer Join Date: May 2004 Location: northern new jersey Posts: 4,158	Re: G body frame swap pics for Heavy. great use of the car oliner i have done the same thing but used 2 sets of arm to hold the front and rear sections so i could ajust the legnth and then used the caroliner meauring system to make sure it was perfect befor welding the new rails in. __________________ cars,bikes,booze and broads the rest of all my money i pissed away

06-06-2006, 07:45 PM	#3
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	Re: G body frame swap pics for Heavy. These next pictures show the new rails installed. DONT MIND THE RUST! We ran out of room, so it got shoved out in the rain. The frame will get sand blasted & painted before I set the body back on. At the front the orig. rail was stager cut, and the new rait was set inside the orig rail. It was plug welded thru the outside of the orig rail, seam welded then 1/8" plate was cut and formed to close off the two sections. The one mistake that was made was in the kick up. Cheri got ahead of herself and welded the kick up without sleeveing the inside. (I had 19 other students, can't watch em all, all the time!) Not a big deal, but I like over kill, so I'll be gusseting, or fish plateing that joint later. In the rear the new rail was kicked out and that joint was sleeved on the long sides(sort of an internal gusset) You can see the plug welds that go into the inside gusset plates. Also the joint was set up with gaps so that the weld penitrates the internal plates. __________________ I have never completely understood anything Last edited by Tinbender; 06-07-2006 at 10:39 PM.

06-06-2006, 07:48 PM	#4
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	Re: G body frame swap pics for Heavy. Not sure what happened to the pics Hang on I gotta resize! __________________ I have never completely understood anything

06-06-2006, 08:09 PM	#6
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	Re: G body frame swap pics for Heavy. Yeah, the car-o-liner is great. When she cut out the rails it didn't move a bit! Still have some work to do. The frame will get a X member at the back of the cab, and a trans X member. And of course a new rear section to mount the bed. I have 100 bucks in steel, and 25 in gas and wire. Paid 350 for the car. My daughter drove it almost two years. I know some of you out there don't like clips, or frame swaps. That's fine. Do what ever you want. For a lot of us, and a lot of cars they are a very viable swap. When I first clipped this truck I bought a running driveing nova for 75.00 I had her on the road for less than 2 grand. I drove it for 5 years and had to replace the idler arm, and front pads. Spent less than 50 bucks! As for this swap, I had the malibu. It ran and drove and road great. Got it back when my daughter bought a honda! I always thought ,man if my Stude only drove like this. Now it will! __________________ I have never completely understood anything

06-07-2006, 08:43 PM	#7
Hackerbilt Old School HAMBer Join Date: Aug 2001 Location: St.Johns,Nfld,Canada Posts: 3,780	Re: G body frame swap pics for Heavy. Excellent and interesting! BttT where this kinda tech should be. Cheri rocks! She's off to a great start by the look of her work on this build. __________________ Bill

06-07-2006, 09:52 PM	#8
wayfarer Alliance Member Join Date: Oct 2003 Location: Spokane, WA Posts: 1,525	Re: G body frame swap pics for Heavy. Looks good Eric. I was wondering if you still had the bulletnose, but I see it in one of the pictures.

06-07-2006, 10:16 PM	#9
crash 51 Grenade Inspector Join Date: Feb 2005 Location: FTW,TEXAS Posts: 362	Re: G body frame swap pics for Heavy. Tinbender. Awesome Info. I Was Set To Clip A 50 Chev Pu Next Week. I Found A 84 Monte For $400 That I May Just Put The Whole Frame Under The Truck. Can You Send Your Students To Texas On A Feild Trip For About Two Weeks? __________________ Customs by Crash Lucky 13 car club

06-07-2006, 10:25 PM	#10
Turbo442 Member Join Date: Nov 2005 Location: Vacaville, CA Posts: 642	Re: G body frame swap pics for Heavy. This is a really cool post. I like the different approach you took with narrowing the rails so it woud work. I have an 84 Cutlass with a Grand National driveline, it has the same chassis. The G-bodies have a ton of factory parts to make them handle and a large aftermarket following. You can get lowering springs, dropped spindles (S-10 spindle is the same), upgrade to larger 12" rotors and larger sway bars. If yours didn't have a rear sway get a $10 one at the junk yard and bolt it on, the holes are already drilled in the lower arms. Speaking of control arms, the rears can be "boxed", just weld a flat piece of steel, or you can buy tubular ones. This will help with handling as well as acceleration. It really does make a difference in the handling as without they feel kinda loosey goosey. I put an IROC Camaro steering box in mine for fast ratio steering. I have done all these upgrades to mine. It handles awesome and stops great as well. Oh and in the rear another mod people like to make is to notch the rear frame rail where it goes over the axle. You just cut and replace the metal with thicker plate but you cut it back so you have a few inches left. I had mine done so I could fit some 315/35/17's which are about 13" wide tires on a 10" rim. Anyway, hope I didn't hog your thread. I just wanted to say there is a lot of potential and options in this chassis. Oh, and the frames are already drilled for Buick, Chevy, Olds or Pontiac motors and all parts are readily available.

06-07-2006, 10:32 PM	#11
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	Re: G body frame swap pics for Heavy. Actually I sold the the bullet nose to the refinish instructor. Hated to let it go but I have far too many projects. Dan, the new owner is one of the best fabricators I've ever known, so I can't wait to see what he does with it. Crash51, they are out for the summer in a week. I dont care where they go, as long as they go! They have been a good group, but I'm ready for summer, and a new group next fall. __________________ I have never completely understood anything Last edited by Tinbender; 06-07-2006 at 10:37 PM.

06-07-2006, 10:37 PM	#12
Tinbender Senior Member Join Date: Mar 2001 Location: Spokane WA. Posts: 2,318	Re: G body frame swap pics for Heavy. Turbo442, thanks,good info. I'v got 15X10 slotted mags that fit nice for the back. I may do some of the upgrades you mentioned. This truck is just going to be a driver, but you know how it goes, it's hard to leave them alone! __________________ I have never completely understood anything

06-07-2006, 11:53 PM	#13
Turbo442 Member Join Date: Nov 2005 Location: Vacaville, CA Posts: 642	Re: G body frame swap pics for Heavy. No problem.If you have any questions or want to know some more sources for info./parts let me know. Did you know S10 springs work well in the front? Stiffer and you can cut them to lower them. Camaro springs work well in the rear.

06-08-2006, 12:17 AM	#14
doctorj928 FNG Join Date: Dec 2005 Location: spokane wa Posts: 17	Re: G body frame swap pics for Heavy. hey eric its looking good i will have to stop by before you get out for the summer and check it out i havent been by in a while jeff

06-09-2006, 11:57 AM	#15
heavy Grenade Inspector Join Date: Mar 2006 Location: blum,texas Posts: 318	Re: G body frame swap pics for Heavy. Big help tinbender thanks!

01-10-2007, 04:10 PM	#16
don meyer FNG Join Date: Jun 2006 Location: florida Posts: 5	Re: G body frame swap pics for Heavy. I welded the G-body front clip(cut about 1 to 1 1/2" behind the lower A-arm) to the Chevy trk AD frame. Works like a dream. I also used Moog lowering springs & Camaro iroc-z box.

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