Crossmember Question
Thread Starter
Racer
Joined: Apr 2001
Posts: 395
Likes: 0
From: Shoreline WA
Crossmember Question
While installing headers yesterday on my 78, I noticed the crossmember was different from what I had seen in the AIM. I was exptecting it to have two cutouts for the exhaust to pass through, like this:
---0--0---
instead this is what mine looks like:
Was this a production change on late 78s, or was mine changed when the previous owner swapped out the engine and transmission? Anyone running trual duals with this crossmember?
Thanks,
Mike
---0--0---
instead this is what mine looks like:
Was this a production change on late 78s, or was mine changed when the previous owner swapped out the engine and transmission? Anyone running trual duals with this crossmember?
Thanks,
Mike
Pro
Joined: Feb 2003
Posts: 582
Likes: 0
From: Ashaway RI
Originally Posted by Older Than Dirt
That pic looks very similar to the one on my 81 auto. I have modded it though for the ROD that's in it now.
looks similar to the one on my 81. Mid America makes a dual system that passes both pipes down the side with the relief.
Burning Brakes
Joined: Aug 2002
Posts: 1,146
Likes: 10
From: Scottsboro Alabama
Originally Posted by bertmeister
looks similar to the one on my 81. Mid America makes a dual system that passes both pipes down the side with the relief.
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Pro
Joined: Sep 2002
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From: Dickinson (Houston) Texas
Racer
Joined: Apr 2004
Posts: 401
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From: IL
Do you have any close up pictures of the frame bracket for the trans crossmember? Adding this type of crossmember to a earlier C3 would look nicer than hacking up the old one and brackets to it to make it removeable.
Thanks
Thanks
Thread Starter
Racer
Joined: Apr 2001
Posts: 395
Likes: 0
From: Shoreline WA
Since it is an automatic, the crossmember is bolt-in. I am already inquiring about gettting the original style. Trying some other members in the "C3 Parts" that were parting out their 74 to 79 automatics. There are also a couple Corvette Salvage yards in the area I am trying.
Mike
Mike
Melting Slicks
Joined: Oct 2001
Posts: 2,320
Likes: 2
From: Salem Oregon
Originally Posted by matchframe
Racer
Joined: Dec 2004
Posts: 298
Likes: 1
My 80 Auto came with the side hump to clear the pipes. I have replaced with a 74 auto crossmember with the ----0--0----. Am putting headers with true duals. Also '80 auto and 4 spd both used a removable x member and a bolt on z bar bracket (and 81). I don't know about 78 or '79.
Melting Slicks
Joined: Aug 2004
Posts: 2,897
Likes: 227
From: Oakbank Manitoba
You can switch back....it will bolt in. The double O style was stock on up to 79 year cars. My 1980 Corvette has the older style now with true dual exhaust. If you buy a used one.....remember to ask for the perch as well. The older Vettes with turbo 400s didn't need the perch as the mounting point was directly on top of the crossmember. The turbo 350 crossmembers have a mounting point that is in front of the crossmember......thus the perch is required If you convert to a 700R4 then a special modified perch can be bought from Bowtie Overdrives. Or you can opt for their tubular crossmember for 700R4 conversions. With this one your killing two birds with one stone!
Pro
Joined: Sep 2002
Posts: 653
Likes: 0
From: Dickinson (Houston) Texas
Originally Posted by GasketDude
Do you have any close up pictures of the frame bracket for the trans crossmember? Adding this type of crossmember to a earlier C3 would look nicer than hacking up the old one and brackets to it to make it removeable.
Thanks
Thanks
Passenger side:
This is the end of the crossmember. There is a bolt that goes through the bracket, and 2 bolts that go into the bottomside of the frame:
www.bigdogvettes.com
Racer
Joined: Dec 2004
Posts: 298
Likes: 1
Sometime an early prior to 76 crossmember doesnt quite line up with the side frme mounts, you have to slightly open the frame hole. I do mean slightly. I had to do it on my "80 with a 74 x member. There have been other posts about the same problem. Thats how I found out I thought i had a bent x member but tried 2 different ones and had same thing.