Frame Differences between years? Bent frame on my 81
Thread Starter
Drifting
Joined: Jan 2003
Posts: 1,809
Likes: 10
From: ST LOUIS MO
Frame Differences between years? Bent frame on my 81
I bought a project car and it has a bent frame. It's an 81 coupe. So, before I start hunting for a new frame, I tried searching on here to see if any C3 frame would work or if I need an 80-82 frame. I saw a link that showed a couple of the minor differences, but can't find anywhere that says any C3 frame, or specifically the 80-82 frames? Mine was put into a ditch in the pass front corner. So, pass front rail, front crossmember, and lower control arm mounts are bent at a minimum.
Thread Starter
Drifting
Joined: Jan 2003
Posts: 1,809
Likes: 10
From: ST LOUIS MO
Thanks. So, if cutting/welding doesn't bother me, say if I found a front frame section from any year C3, would it work? Or are they physical differences between the years? Like mounting spots are different, body mount holes, etc.
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
If you have the ability to cut and weld, why don't you repair the frame you have..? I've seen some pretty screwed up frames in my life, and every one of them has been repairable with a frame machine and some cutting & welding. If I were you, I'd do a pull on your existing frame to get all the datum points into the correct locations. Then, cut out and replace any sections that are kinked or buckled after the frame is actually straight (with the body off the frame, of course). Almost every section of the frame is available as a reproduction part.
Lars
Lars
Race Director
Joined: Apr 2009
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From: Charlotte NC
If you have the ability to cut and weld, why don't you repair the frame you have..? I've seen some pretty screwed up frames in my life, and every one of them has been repairable with a frame machine and some cutting & welding. If I were you, I'd do a pull on your existing frame to get all the datum points into the correct locations. Then, cut out and replace any sections that are kinked or buckled after the frame is actually straight (with the body off the frame, of course). Almost every section of the frame is available as a reproduction part.
Lars
Lars
...could not have written it better myself. It will most definitely need to be straightened first...before any cutting....and I do not need to see it to comment that way.DUB
Race Director
Joined: Apr 2009
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From: Charlotte NC
Even though using a frame table is the best method (speed and precision)...it is not your only option. The whole point is to keep it where you want it before welding is completed..as I know you would agree. If you are a welder...than you can construct out of box tubing and angle iron and network that could hold the frame together as needed in correct points so the front clip frame sectioned can be welded in place.
Decisions, decisions, decisions.....many of my customers are faced with this quite often due to damage that needs to be repaired and what "some" think it should cost is often times way off from reality.
Best of luck in your search or decisions you choose to make.
DUB
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Melting Slicks
Joined: Jul 2010
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From: McGrady NC
St. Jude Donor '15-'16
How and where is it bent? Damaged in a wreck badly? It's really hard to offer the best advice without a little more info.
78-82 should be very similar except for the rear end mounting. The bumper impact bars should be the same since the bumpers mount very similarly. The tranny crossmember should even be the same as it changed between 77 and 78.
You are looking at a bunch of work and $$$ no matter how you look at it. Unless you got a real deal in your car perhaps you would be better off locating a better starting point and using the one you have now as a donor. I'm doing a 77 that exact way.
78-82 should be very similar except for the rear end mounting. The bumper impact bars should be the same since the bumpers mount very similarly. The tranny crossmember should even be the same as it changed between 77 and 78.
You are looking at a bunch of work and $$$ no matter how you look at it. Unless you got a real deal in your car perhaps you would be better off locating a better starting point and using the one you have now as a donor. I'm doing a 77 that exact way.
Instructor
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From: Cincinnati OH
Team Owner
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From: Southbound
Cruise-In II Veteran
Race Director
Joined: Apr 2009
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From: Charlotte NC
Can this frame be fixed....YES....without any doubt (using the photo posted).
The issue is not if it can be fixed or not...because I know that it can. BUT...the question is how much $$$ and time do you wan to put into it. Because repairing it can run as much as a used frame if not more to repair this frame...due to the right side is still unknown. This is why I wrote "kinda".
It all depends on those in your area who do frame repair....and what the hourly rate is for doing so. For sure...the body who have to come off for me to fix it. Much easier to measure and secure it for pulls and stretching and so on.
DUB
Thread Starter
Drifting
Joined: Jan 2003
Posts: 1,809
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From: ST LOUIS MO
thanks guys. I'm going to talk to a body shop this week to see what he thinks. guy is semi retired and just does side projects when he feels like it. Hes doing quarters on my dads 67 El Camino right now. body will be coming off the frame regardless so might as well get some estimates.
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From: Millington Illinois
St. Jude Donor '08-'09
Safety Car
Joined: Nov 2008
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From: Seattle Washington
I think You need an 80 82 Frame. I think the front bumper mounts are a bit different. The X member is different and for sure the Rear End Mounts. I'd search Craigslist here in NW or the West Coast because we don't get much Rust. $2500 for a Used Frame ? For get it, I have seen a complete 82 minus body for $1250, that was with the Engine Trans Rear and Suspension. I was offered a 82 with no Title in ruff condition for $500 not to long ago. There is a Guy who Parts out C3's in Chehalis Wa and he probably has so many laying around he doesn't know what to do with them. Keep in mind that there are only so many people willing to change out a Frame on a 30 year Car that is not a collector idem, and frames are priced accordingly.