C3 Chassis reliability
Thread Starter
Race Director
Joined: May 2004
Posts: 11,920
Likes: 2
C3 Chassis reliability
Question to all ye Hot Rodders and racers...
1)Where does the C3 chassis take most of its strain?
Secondary areas?
2)What is the best way to strengthen it or lessen the strain on it
a)Welding
b)Suspension mods
3)How to best accomplish the above?
4)Price of mods ratio to effect of those mods
Thanks!!
1)Where does the C3 chassis take most of its strain?
Secondary areas?
2)What is the best way to strengthen it or lessen the strain on it
a)Welding
b)Suspension mods
3)How to best accomplish the above?
4)Price of mods ratio to effect of those mods
Thanks!!
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
1:
front suspension mounts, check for cracks along the channels and the welded brackets at the rear of the crossmember.
the area where the frame kciks out after the front wheels, especially where that big hole for the power steering ram mounting bracket stud plates (geez what a word) is.
rear kickup area, gm addressed some of that with the extra bracing on 69+ frames.
2: welding, gusseting, checking factory welds (the horror!) and doing a better job than the factory did.
3: buy a welder and practice till you can make strong, good penetrating and good looking (spatter free and non porous) welds. It takes practice, and get a mig machine that uses gas, not flux core. OR buy a case of beer for a buddy that knows how to weld and want to weld your stuff (this isn't done within 1 day!)
Steel is pretty cheap (well..it's gotten more expensive, dobule almost...damn chinese) the welder is not cheap though
knowledge...well this board is free. Do a search on frame strengthening & gussetting., there are some interesting threads out there.
front suspension mounts, check for cracks along the channels and the welded brackets at the rear of the crossmember.
the area where the frame kciks out after the front wheels, especially where that big hole for the power steering ram mounting bracket stud plates (geez what a word) is.
rear kickup area, gm addressed some of that with the extra bracing on 69+ frames.
2: welding, gusseting, checking factory welds (the horror!) and doing a better job than the factory did.
3: buy a welder and practice till you can make strong, good penetrating and good looking (spatter free and non porous) welds. It takes practice, and get a mig machine that uses gas, not flux core. OR buy a case of beer for a buddy that knows how to weld and want to weld your stuff (this isn't done within 1 day!)
Steel is pretty cheap (well..it's gotten more expensive, dobule almost...damn chinese) the welder is not cheap though
knowledge...well this board is free. Do a search on frame strengthening & gussetting., there are some interesting threads out there.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Originally Posted by Twin_Turbo
1:
front suspension mounts, check for cracks along the channels and the welded brackets at the rear of the crossmember.
the area where the frame kciks out after the front wheels, especially where that big hole for the power steering ram mounting bracket stud plates (geez what a word) is.
rear kickup area, gm addressed some of that with the extra bracing on 69+ frames.
2: welding, gusseting, checking factory welds (the horror!) and doing a better job than the factory did.
3: buy a welder and practice till you can make strong, good penetrating and good looking (spatter free and non porous) welds. It takes practice, and get a mig machine that uses gas, not flux core. OR buy a case of beer for a buddy that knows how to weld and want to weld your stuff (this isn't done within 1 day!)
Steel is pretty cheap (well..it's gotten more expensive, dobule almost...damn chinese) the welder is not cheap though knowledge...well this board is free. Do a search on frame strengthening & gussetting., there are some interesting threads out there.
front suspension mounts, check for cracks along the channels and the welded brackets at the rear of the crossmember.
the area where the frame kciks out after the front wheels, especially where that big hole for the power steering ram mounting bracket stud plates (geez what a word) is.
rear kickup area, gm addressed some of that with the extra bracing on 69+ frames.
2: welding, gusseting, checking factory welds (the horror!) and doing a better job than the factory did.
3: buy a welder and practice till you can make strong, good penetrating and good looking (spatter free and non porous) welds. It takes practice, and get a mig machine that uses gas, not flux core. OR buy a case of beer for a buddy that knows how to weld and want to weld your stuff (this isn't done within 1 day!)
Steel is pretty cheap (well..it's gotten more expensive, dobule almost...damn chinese) the welder is not cheap though
knowledge...well this board is free. Do a search on frame strengthening & gussetting., there are some interesting threads out there.
Advanced
Joined: Nov 2003
Posts: 77
Likes: 0
From: Garland Texas
I'm doing a frame off and just had my frame welded in several places. (Couldn't believe how bad the factory welding was.) Didn't use a frame jig, but didn't weld long sections. Hopefully, it didn't warp because it's at the powder coater now. I had a lot of cracks in the the mentioned areas. So I would definitely recommend having the frame welded anywhere you think it is weak (about everywhere). I plan on doing some cross bracing between the front spring towers and to triangulate the rear areas under the seats.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
The trick is to only weld short sections, the factory used skip welds and on the later frames the skips are very small and easily to weld without a chance of warpage if you alternate where you weld. The earlier frames are a bit worse, the skips are much larger there. I didn't use a jig but I did measure the frame beforehand to check for straightness and afterwards nothing had changed at all so it will be just fine.
