Chevy Nova Forum banner

1 - 20 of 52 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
I have a 63 Nova SS convertible that I just installed a new 4 link setup in. It is a Full Tilt Street Rod 4 link setup. At some point after removing all the original rear suspension I noticed that both quarter panels have buckling just in front of the rear wheels. We installed sub frame connectors as well just in case anyone is wondering. When we rest the car on stands under the front Heidts sub frame and just under the rear section of frame just in front of the bumper the buckles disappear. We thought maybe it was because we welded in the sub frame connectors with the car on the lift so we cut them loose with the car on stands. They did separate about twice the distance of the cutoff wheel. We then mig welded them back in place with the buckles gone. When we set it back on the tires they came right back. I spoke to Clay at Full Tilt and he said he had not heard of this issue from any of his customers whether hardtop or convertible. Has anyone had or heard of this issue? Looking for any help we can at this point.
 

·
Registered
Joined
·
1,068 Posts
I dont think theres a real right or wrong solution as discussed in the above thread. It seems to me these tin pepsi cans relied heavily on the leaf spring suspension to push back evenly on both sides of the rear quarter. The 4link is just a different animal n changes everything so to speak. But in that thread, i believe it was Shane, came up with an adjustable strut he burned into trunk compartment. Im thinkn someday aftr i shake my car down n get final ride hieght, etc, id like to try his idea. Looks easy enuff n fully adjustable
 

·
Super Moderator
Joined
·
3,839 Posts
The thickness of the metal is not the issue. They are hardly tin Pepsi cans, but 400+ horses, limited slip 4-links and foot-wide tires are more than they were built for. Lots of seriously thought-out arrangements to keep even convertibles, flimsy from day one, together have been designed by shops and home garage chassis builders that work.
 

·
Moderator
Joined
·
6,404 Posts
This was one of the threads with a discussion on the problem that some have had.
https://www.stevesnovasite.com/forums/showthread.php?t=665087

I was talking to some guys at a car show this past summer and the one person suggested using body panel glue to ad stiffening to the area that is prone to the buckling. I thought that might be a good idea. Best done prior to the 4 link install. A quarter panel could be cut up to match the area and it would have the correct profile of body lines. Tough though to get the size needed into the quarter panel and then to glue it in place. Thinking out loud here. But use paper on the outside of the quarter to determine the size bearing in mind that it has to be able to get inside the quarter panel. Remove the rear side window and slide the metal through the window opening to test fit. Once fitted, clean and apply glue to the inside of the quarter panel and slide in the stiffener. Block in in place until the glue hardens. Maybe it's a plan and maybe it's not the answer.
 

·
Registered
Joined
·
1,068 Posts
The thickness of the metal is not the issue. They are hardly tin Pepsi cans, but 400+ horses, limited slip 4-links and foot-wide tires are more than they were built for. Lots of seriously thought-out arrangements to keep even convertibles, flimsy from day one, together have been designed by shops and home garage chassis builders that work.
Feel free to elaborate on these other solutions. Im trying to solve this problem before i invest 10k+ into paint n body work aftr my build is running n complete. I get what your saying bout modifying a 1960s 60mph 200hp sunday driver. Alot of the chassis work performed on these cars typically stiffens everything up in every direction. The real issue is simply the difference in how a leaf spring distributes/suspends wieght vs. a 4link set up. Which i believe the 4link is more about keeping the rear in check and wieght transfer. Than all that wieght is simply put on a tite fulcrum point aka coil overs. Obviously this is not an issue eith full framed vehicles. Thats what i meant by "tin can". Im more interested in some of the solutions to this as its quite common to see more in more 4link systems going in as bolt on kits are the norm now. The only solution im aware of is that strut that Shane built in his trunk. And its "tuneable". Im not saying there isnt other solutions, id just like to see what else has worked and been done out there. Im most likely gunna give those strut ideas a shot bcuz in my mind it makes perfect sense as it mimics at least half of the leafsprings original job. The glue n panel gig kinda seems more like a band aid to me...an aftr thought imho. The strut set up relieves or counters the actual uneven pressure thats created.
 

·
Registered
Joined
·
281 Posts
I wonder if tubbing along with the 4link install has a bearing on the buckling issue. The inner fender well is part of the rear quarter panel strength.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #11
Last night my Fabricator cut the frame just over the differential. He then slowly lifted the frame at the rear of the car until the buckles disappeared and then went a little further. Then he drove a 3/16" wedge in the area and tig welded it all back together. He then set the car back on the ground and no more buckles. I would love to see what Shane did with that strut in the trunk but cannot seem to find the link.
 

·
Moderator
Joined
·
6,404 Posts
Last night my Fabricator cut the frame just over the differential. He then slowly lifted the frame at the rear of the car until the buckles disappeared and then went a little further. Then he drove a 3/16" wedge in the area and tig welded it all back together. He then set the car back on the ground and no more buckles. I would love to see what Shane did with that strut in the trunk but cannot seem to find the link.
https://www.stevesnovasite.com/forums/showthread.php?t=665087
 

·
Registered
Joined
·
1,596 Posts
I mini rubbed mine and did the CBR 4 link. I didn’t remove the leaf springs until the mini tub was complete and the frame rails were boxed back in. I had no buckle issues.
 

·
Registered
Joined
·
540 Posts
I have the TCI bolt in 4 link in my car (no minitub) and no issues. Maybe the minitub amplifies the issue.
 

·
Registered
Joined
·
394 Posts
I have the TCI TQArm and tubbed it up to the frame rail. I did have to notch the frame rail for disc brake caliper clearance (about 6-8" in length) and I believe we used a piece of 1/4" steel for that section of frame rail. The frame notch occurred after doing the tub and is in front of the axle as the caliper faces forward. It has not buckled yet (and may not) but has only been driven in driveway. Perhaps the short length of frame rail mod is why mine hasn't been an issue but the trunk brace bar may be cheap insurance.
 

·
Registered
Joined
·
336 Posts
I have the TCI TQArm and tubbed it up to the frame rail. I did have to notch the frame rail for disc brake caliper clearance (about 6-8" in length) and I believe we used a piece of 1/4" steel for that section of frame rail. The frame notch occurred after doing the tub. It has not buckled yet (and may not) but has only been driven in driveway. Perhaps the short length of frame rail mod is why mine hasn't been an issue but the trunk brace bar may be cheap insurance.
Do you know how wide your rear end housing is from housing end to end?

My son & I are going to install CBR 4link & DSE mini tubs in my '67. I also have a new Moser 12bolt housing with the CBR 4link brackets already welded on by Moser. The housing ends are tack welded on to allow for easy shortening if necessary. I'm also going to be using rear disc brakes & your comments about notching the frame really got my attention!

Mike
 

·
Registered
Joined
·
344 Posts
Does anyone have any real pictures of the buckling that occurs and the aftermath of it? I've never actually seen it first-hand.
 

·
Registered
Joined
·
281 Posts
I’ve got the TCI 4 link with subframe connectors in my 67. I did not mini tub it. Have 2,000 miles on it and been down some pretty rough roads with no buckling on the rear quarters. That’s why I thought it might be more prevalent on tubbed cars.
 
1 - 20 of 52 Posts
Top