Frame weakness ??? new verses original ???

[JeffP1167]

I'm getting around to getting started on my 82 frame conversion. Is my original frame weak (don't think it has rust) .... I really don't like the round tube frames, I like the square tube versions better.

So without welding and gusseting would my original frame still have weak areas after it's conversion? Or would it be best to just by a frame already setup for c4 suspension?

I've seen a few threads on here about major welding on original frames so that alone makes me think just either sell my original rolling frame and buy a after-market frame.

 

[SuperBuickGuy]

read the Chevrolet power article in downloads - then make up your mind... background to get you interested, GM gave pointers on how to make Corvettes into race cars - enlightening

 

[BBShark]

Don't know if this is true or not but some say that the early frames are stiffer than the later C3 frames. Thicker metal, better welds, etc? If they are stiffer, it's probably not much.

Outside of adding a cage, there is probably not much that could be done to make a large improvement in stiffness.

 

[SuperBuickGuy]

there's one hole in the frame that GM said "fill", it's behind the steering box bolts... that made a noticeable difference when I filled mine - of course, this is all seat-of-the-pants testing; so it could also be that I just thought it is better...

 

[mrvette]

IMO, they way MY '72 vert reacted to various changes....in order of importance, not necessarily as to when it was done.....


Wheels/tires.....easy hands down tossed the 15" and went with 17x9.5 rims...

Cross support between A arms up front.....HUGE improvement, different car, I was shocked.....

Shocks, went from tough riding KYB to a set of Bilsteins from VBP, improved the ride a NICE amount.....and of course a plastic rear spring....

Brakes, but that's another thread....

Rack steering, but that's another thread.....



:bump::goodevil:

 

[427Swede]

If you buy an aftermarket frame I would suspect it to be prepaird and ready for special suspension parts probably supplied by the frame manufacturer, or, are there aftermarket C3 frames prepped for a C4 suspension??
Anyway it sounds really expensive in comparison to keeping your old frame and make some modifications on it to get it stronger.
What is your budget on the project?

If you look in the Chevy Power book about frame modifications, as already mentioned, there are some very good advices that can be applied without too much problem. Fully welding and gusseting your old frame will give it enough strength.
They were running these cars in L88 configuration on the tracks with the standard frame, of course modified, but anyway!

//Daniel

 

[clutchdust]

I just read last night an article in the latest issue of Vette magazine about the original owner of an L-88 car. He said one of the things that impressed him so much about the L-88 is it had so much torque. So much torque that when he laid on the gas it would flex the frame enough that his 'door ajar' light would come on.
Granted, that was a stock frame but the earlier frames were indeed thicker than the later frames, and presumably stiffer. C3 frames are spaghetti.

 

[SuperBuickGuy]

I just read last night an article in the latest issue of Vette magazine about the original owner of an L-88 car. He said one of the things that impressed him so much about the L-88 is it had so much torque. So much torque that when he laid on the gas it would flex the frame enough that his 'door ajar' light would come on.
Granted, that was a stock frame but the earlier frames were indeed thicker than the later frames, and presumably stiffer. C3 frames are spaghetti.

My last project car was a 70 Buick Skylark .. put enough juice under the hood and you'll lift the front tire (all 3 other tires solidly on the ground). Lift the front tire and you'll crack the windshield. While yes, there's much to be done, they're also a lot better than their siblings and competitors of the day... That said, a couple hundred pounds of DOM tubing and problem solved

 

[BBShark]

I'm getting around to getting started on my 82 frame conversion. Is my original frame weak (don't think it has rust) .... I really don't like the round tube frames, I like the square tube versions better.

So without welding and gusseting would my original frame still have weak areas after it's conversion? Or would it be best to just by a frame already setup for c4 suspension?

I've seen a few threads on here about major welding on original frames so that alone makes me think just either sell my original rolling frame and buy a after-market frame.

The round tube frame looks nice but I don't see any information that quantifies how much stiffer it is. I asked them a while back and they couldn't tell me the torsional strength of the C3 frame or the % improvement of their frame. Or even simple things like weight difference, etc.

That's too much money to pay for something without some assurance that it is an improvement.

 

[daveL82]

I have an 80 with no rust and yes the frames are thinner steel. Mine stared to bend the box section under the doors from using a floor jack for 30 years on it. I ended cutting out the bottom and welding in new steel. Two things over the years made the chassis very stiff: a welded in rear roll bar and solid motor mounts. Not as good as the new cars bit a huge improvement