4 speed into an Auto Frame
Thread Starter
Instructor
Joined: Mar 2015
Posts: 151
Likes: 12
From: Burleson Texas
4 speed into an Auto Frame
Is this a direct bolt in or is some kind of adapter needed?
I have a 72 auto frame and a 73 manual frame. I plan on using the 454, 4 peed, and rear end components including sway bar from the 73 for doing a frame off on my 72 convertible.
Thanks
Jim
I have a 72 auto frame and a 73 manual frame. I plan on using the 454, 4 peed, and rear end components including sway bar from the 73 for doing a frame off on my 72 convertible.
Thanks
Jim
Team Owner
Joined: Sep 2006
Posts: 31,230
Likes: 4,324
From: Westminster Maryland
Hi Jim,
Some folks doing the 4-speed/automatic change find locating the exact position for the clutch z-bar bracket to be a challenge.
So be careful to measure well before you remove the bracket from the 73 frame to weld it to the 72 frame.
Good Luck!
Regards,
Alan
Some folks doing the 4-speed/automatic change find locating the exact position for the clutch z-bar bracket to be a challenge.
So be careful to measure well before you remove the bracket from the 73 frame to weld it to the 72 frame.
Good Luck!
Regards,
Alan
Tech Contributor
Joined: Jun 2004
Posts: 20,868
Likes: 961
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I put an auto frame under my '69 years ago when I converted to a C4 suspension. I just fabricated a replacement Z-bar bracket and welded it in the same location as on the original frame. One of the easiest issues in the frame swap.
Racer
Joined: Apr 2005
Posts: 484
Likes: 5
From: Madison Wisconsin
I recently did an auto to manual swap in my '73. You will need to weld some tabs on the cross member to support the bracket that moves the trans mount closer to the front, but overall it's not bad and having the removable cross member from the automatic frame is nice if you need to removed the trans in the future.
Good luck, send me a PM if you have any questions. Not an expert, but have gone through the conversion.
Jim
Good luck, send me a PM if you have any questions. Not an expert, but have gone through the conversion.
Jim
Racer
Joined: Apr 2005
Posts: 484
Likes: 5
From: Madison Wisconsin
The cross member mod is actually pretty straight forward. You will need to purchase a bracket that extends the trans mount forward. One end of the bracket bolts to the cross member in the same spot as the auto mount. The other end of the bracket moves the mount forward for the 4 speed. You will also need to purchase two tabs that weld onto the front side of the cross member and then the bracket is supported by these brackets. When I did my conversion. I bolted the bracket to the cross member and trans to locate the tabs and then tack welded them in place. I removed the new bracket and finish welding the tabs to the cross member. I think you can get the bracket and tabs at most of the main Corvette supply shops.
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