Tranny Swap ??????
Tranny Swap ?????? i want to put a 700R4 in my 1980 T/A it has a TH350 right now. besides the drive shaft lenght difference what other problems could i possibly run into. Can i still use my cross member or will i need to get another one?
You will need a throttlecable bracket off of a carburetored 86 so the trans will shift right. I cant remember on the crossmember but i think i reused the stock one but had to shorten the driveshaft
Teching In
Joined: Jul 2006
Posts: 42
Likes: 0
Actually the Th350 that came in Birds is the same length as the 700R4 and the 2004R. I was as surprised as anyone but I have one of each and a short Th400 next to each other in the shop. All same length. The crossmember can be moved back and you can redrill the subframe holes, you have to do that when you install a Th400 in the 77-81s, and the 700 has the mount a bit farther back from the 350. I havent had to shorten a driveshaft yet, just replace yokes.
Getting the TV cable geometry is important, you can get a bracket from a car that had one, or you can buy one from Summit, Jegs, etc since most of the transmission companies have them. If they dont know what you are talking about, a bud of mine in South Carolina can get you hooked up.
The lines are slightly different but they should use the same fittings, you can usually just bend them so they fit. If not it isnt difficult to make new cooler lines.
The lockup is a nice feature to have, and some people have had failures with the converter left unlocked. You can get a controller for it, or wire a 12v source to it with a toggle switch. The toggle switch has the drawback of leaving it on while trying to stop, it makes it rather difficult and will destroy the clutch in the converter if done too many times. Once might be too many FYI.
You wont be able to put it in Low 1(first gear) with the stock shifter, you will either need a different one from a 3rd gen, or 79-87 Monte Carlo, Regal, Gran Prix, Cutlass that had the overdrive trans in it. Other shifters might work, but those will bolt right in for you.
If you have a chevy in it you dont need much else. If you have any other engine you will need an adapter to fit the 700. The adapter might need a 1/4" or so taken out of the driveshaft, depends on how the slip yoke fits and how long the yoke is.
Getting the TV cable geometry is important, you can get a bracket from a car that had one, or you can buy one from Summit, Jegs, etc since most of the transmission companies have them. If they dont know what you are talking about, a bud of mine in South Carolina can get you hooked up.
The lines are slightly different but they should use the same fittings, you can usually just bend them so they fit. If not it isnt difficult to make new cooler lines.
The lockup is a nice feature to have, and some people have had failures with the converter left unlocked. You can get a controller for it, or wire a 12v source to it with a toggle switch. The toggle switch has the drawback of leaving it on while trying to stop, it makes it rather difficult and will destroy the clutch in the converter if done too many times. Once might be too many FYI.
You wont be able to put it in Low 1(first gear) with the stock shifter, you will either need a different one from a 3rd gen, or 79-87 Monte Carlo, Regal, Gran Prix, Cutlass that had the overdrive trans in it. Other shifters might work, but those will bolt right in for you.
If you have a chevy in it you dont need much else. If you have any other engine you will need an adapter to fit the 700. The adapter might need a 1/4" or so taken out of the driveshaft, depends on how the slip yoke fits and how long the yoke is.