Frame Compatibility
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,734
Likes: 276
From: Port Huron MI
Frame Compatibility
I know one of the Wiley Coyote super genius folks on here knows this answer:
Will a 78 frame work under a 68 body? I know the 68 has several one of a kind features and measurements, but I'm curious if with a few modifications a 78 could be used.
As always thanks for the time and expertise.
Will a 78 frame work under a 68 body? I know the 68 has several one of a kind features and measurements, but I'm curious if with a few modifications a 78 could be used.
As always thanks for the time and expertise.
Safety Car
Joined: Sep 2003
Posts: 4,206
Likes: 8
From: Belmar NJ
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,734
Likes: 276
From: Port Huron MI
Anybody on here ever done a 78 frame under a 68? I know there are some specific to that project quirks. Thought I'd fish for more info before diving into it.
Drifting
Joined: Jan 2012
Posts: 1,908
Likes: 129
From: Fredericksburg Virginia
I personally have a 76 frame that I'm putting under my 70 car.
I know I'll have to "graft" the rear bit from my frame onto my "new" frame.
Personally, 1977 was my cutoff. I was not willing to undertake the more significant modifications necessary in the rear of the frame to adapt a 1978 frame. This involves a considerably "deeper" cut into the dogleg area to suit conversion.
Note the difference in the rear end mount. That makes your weld a primary component in the structural integrity instead of something to just hold the gas tank and bumpers up.
Other than that, you should be good. Depending on if your car is an early or late 68, your existing frame will or won't have the main dogleg gussets. But I don't know that there is anything interfering with those gussets on an early 68 body either way...so it should be fine.
As I said...I JUST went through this. A 1977 and earlier frame will be easier for you to deal with than a 1978 and later frame. A 1974 and earlier frame will be easiest for you to deal with and essentially identical to the frame that is under your car right now.
I know I'll have to "graft" the rear bit from my frame onto my "new" frame.
Personally, 1977 was my cutoff. I was not willing to undertake the more significant modifications necessary in the rear of the frame to adapt a 1978 frame. This involves a considerably "deeper" cut into the dogleg area to suit conversion.
Note the difference in the rear end mount. That makes your weld a primary component in the structural integrity instead of something to just hold the gas tank and bumpers up.
Other than that, you should be good. Depending on if your car is an early or late 68, your existing frame will or won't have the main dogleg gussets. But I don't know that there is anything interfering with those gussets on an early 68 body either way...so it should be fine.
As I said...I JUST went through this. A 1977 and earlier frame will be easier for you to deal with than a 1978 and later frame. A 1974 and earlier frame will be easiest for you to deal with and essentially identical to the frame that is under your car right now.
Last edited by keithinspace; Sep 17, 2014 at 01:45 PM.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
too much work to make it fit
Melting Slicks
Joined: Jan 2012
Posts: 3,033
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From: myrtle beach sc
Army
I have a replacement frame from GM. It was made for 1968-1974 Corvettes. I would not use a 78 frame. Don't forget, in 1975 GM lowered the frame body mounts to accommodate the new rubber mounts that they added because they were putting the harsh riding, steel belted radials on the 75 Vette. Lou.
