Body sag

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Body sag

Postby billetaluminum » Sat Dec 10, 2011 4:31 pm

I have visited this site many times since I bought my Vega and have always enjoyed reading and learning from all the posts. I now have a question and haven't had much luck searching the threads. I have a '71 hatchback that has been backhalfed and has a 10 point cage but no halo bar across the windshield. When they built it in the '90's as a drag car they never included sub frame connectors. The car has just under 500 hp and is in very good shape. It has developed a few chips in the paint on the door edges on the upper 1/3 of the doors. There is a gap when it's sitting but there must be enough flex and sag in the chassis that has allowed it to chip. My plan is to jack it up in the middle to take the sag out then add sub frame connectors. Before I get started I would like any info from anyone that has had to fix this problem. Or if you recall seeing this topic in a thread somewhere steer me in that direction. Thanks in advance.
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Re: Body sag

Postby HAULIN' IT » Sat Dec 10, 2011 10:52 pm

Are these chips at the front of the doors or the rear? Lorne
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Re: Body sag

Postby chevy art » Sun Dec 11, 2011 1:25 am

hey billet i think rockdaddy had this problem like this with his car last year. think his was sagging at the front door-fender separation. just seem to remember this. you may want to check with him art
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Re: Body sag

Postby monzajer » Sun Dec 11, 2011 10:32 am

billet, I think this is the thread Art is referring to. Is this it Art?


About half way down Rockdaddy posted some videos, I think the 2nd vid is more what you are looking for.

Hope this helps.

cheers, jer :mrgreen:

PS: the "chips" , ummmm, I'm imagining these are at the top front of the door area. Is this correct? At the firewall? Like the "frame" is bending in the middle. With 500HP and being drag raced is it conceivable that the front may have tried to come up, but without connectors or more cage the frame was suffering. And then when it hits the track again there is the opposite bending? Kinda up and down will have a serious effect on these somewhat weak "frames".
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Re: Body sag

Postby billetaluminum » Mon Dec 12, 2011 5:42 am

Sorry, I should have been more specific. The chips are at the rear of the door, just below door handle height. There isn't any issues at the gap between the fender and door. Thanks for the input. I checked out those vids and the thread. Thankfully my problem isn't as bad as his. When I pulled up some carpet I discovered that some of the sheet metal around the wheel tub is ripped. So yes it's been in the air because what has happened is the wheelie bar has been forced up against the bottom of the enclosure for the fuel cell pushing it upward and ripping the sheet metal around it and the wheel tub. This is a street car now but I do want to get on top of the flexing issue.
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Re: Body sag

Postby invegarating » Mon Dec 12, 2011 2:44 pm

You said this is a backhalf car,what is the frame material in the rear? Are the chips on the doors on both sides or just the driver side? If the rear frame is not tied to the body well the backhalf itself can move around tearing sheetmetal,especially with an incomplete rollcage
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Re: Body sag

Postby falcon_morris » Thu Jul 19, 2012 6:52 am

Had the same problem with my Vega. Our cars could be twins. I found excessive gap at the top edge of the door toward the front. I think this problem is from the wheels comming back to earth too hard. Show off wheel stands.
Jacked up in middle and let tetter for a couple of weeks. Welded in frame ties with the car in this position. Much better now. Frame shop could have done a better job, but I am fairly cheap.
Also, check for frame spread between front wheels, I had to pull mine in about 3/4 of an inch.
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