can i
Race Director
Joined: Oct 2000
Posts: 12,640
Likes: 3,103
From: Shamong, NJ
Are you talking about using the 79 4 speed, to convert your 80 from auto to 4 speed?
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
Last edited by gbvette62; Oct 29, 2015 at 06:51 PM.
Le Mans Master
Joined: Dec 2009
Posts: 6,397
Likes: 649
From: Saskatoon Saskatchewan
Are you talking about using the 79 4 speed, to convert your 80 from auto to 4 speed?
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
Thread Starter
Instructor
Joined: Jun 2012
Posts: 192
Likes: 0
Are you talking about using the 79 4 speed, to convert your 80 from auto to 4 speed?
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
If so, everything should be a direct bolt in. About the only thing you'll need is an 80-81 4 speed drive shaft. The 79 uses u-joints on both ends, that are a different size, than the ones used on both ends of the 80 automatic drive shaft. The 80-81 4 speed drive shaft uses the same trans u-joint as the 79, and the same rear pinion u-joint as all 80's. You may also be able to get a conversion u-joint, that adapts the 79 drive shaft, to the 80 rear pinion.
You will also need the 80-81 clutch cross shaft frame bracket. Unlike the 79 bracket, which is welded to the frame, the 80-81 bracket bolts on. You may have to change the lower speedometer cable too.
You shouldn't need to modify the hole in the floor either. I believe the auto shifter, sits in the exact same size hole, as the 4 speed shifter comes through.
The only thing you really may want to check out before going forward, is which trans is in the 79. Some 79's came with a Saginaw 4 speed, while others used the Borg-Warner Super T-10. The Saginaw is not a great trans, and really isn't ideal, especially if you plan any kind of performance upgrades to your engine.
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
and yes, you do need to cut the hole for the shifter.
Last edited by qwank; Oct 30, 2015 at 08:16 AM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
The setup can usually be found for 700 to 1000. If this parts car is under that and you have the means to drag it away, i would get it. Even if the saginaw trans, it is a come-up over the automatic. And you can always find a t-10 later and re-sell the sag...
