4 speed b body to a body

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cmac64dart

cmac64dart

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Just curious how much more work is involved with installing a newer b body 4 speed in an early a body. thanks .
 
No, it has a 3 on the tree. My concerns are more with the tail section length differences with linkages. thanks, chris
 
It's been done with adapters shorter drive line and such. I would think by the time you spent the money for the adaptive parts and the large amount of time to figure it out - you'll be wishing you just got the correct one. I'm sure you'll want a new/ different steering column ?
 
I figured I would do the column at a later date. Is this going to be an issue? I mean other than looking at the shifter? I had thoughts of possibly leaving the tree speed in but was told the early a 3 speeds wont take the v8 punishment and it looks like a pain to find the v8 bell housing needed. Not to mention floor shifter just seems the right way to go
 
The B 4 speed is same length as a 727, the A 4 speed is same length as a 904. So, length is not "the" big problem. The big problem is the location of the shifter mount pad, or pads in the case of a 70 / later B/E gearbox. There is a diagram, floating around, somebody made an adapter bracket. I have no idea what that might do to the "floor plan."

Here:

http://www.bigblockdart.com/techpages/techindex.shtml

which leads to

http://www.bigblockdart.com/techpages/abconv.shtml

However, the earlier "B only" gearbox, with only the front mount, would be harder, as it's in the road of the crossmember
 
I'm not sure when the change to slip yoke happened and you mentioned earlier a body.
 
If the drive-shaft get's to be too short, it get's hard to find a satisfactory driveshaft angle that will nullify a phase vibration, especially with soft rear(street) springs.

Having said that, I bolted a B/E A833 into my 68 Barracuda. (I know it's not a 1st gen, but..) I had to fab up my own shifter mounting plate and also new HD shift-rods. Since I had to do that, I decided to pull the shifter way back between the buckets and really high up. The top shifter bolt goes in from the cockpit.Now I can put some real power into the short stick. Missed shifts are history.I'm not going back to the A-body tailhouse, ever.
 
AJ/FormS said:
If the drive-shaft get's to be too short, it get's hard to find a satisfactory driveshaft angle that will nullify a phase vibration, especially with soft rear(street) springs.

Having said that, I bolted a B/E A833 into my 68 Barracuda. (I know it's not a 1st gen, but..) I had to fab up my own shifter mounting plate and also new HD shift-rods. Since I had to do that, I decided to pull the shifter way back between the buckets and really high up. The top shifter bolt goes in from the cockpit.Now I can put some real power into the short stick. Missed shifts are history.I'm not going back to the A-body tailhouse, ever.
Click to expand...
Or someone could shift from the back seat for you ! :D
I was wondering how long it would be til we were going to hear from you on this one ? :happy1:
 
The early models 4-speeds had ratios of 3.09-1.92-1.40-1.00. The 1-2 split is a bit wide, but allows a 14% reduction in rear gear for the same first gear giddy-up. This means you don't have to run 4.10, but rather 4.1 less 14% equals 3.55;surprise! Unfortunately IIRC this 3.09low gear set did not make it into the slip-yoke tranny, which means you will need the later mainshaft and it's tail house, and will have to do a bit of swapping.I have done this swap and can testify that the 3.09 gear will/does work very well with 3.55s. In your Lightweight gen1 car I would recommend 3.23s as being sufficient to launch a streeter with authority, and the extra gear will make hiway cruising much more bearable. The 3.09 x 3.23 = the same starter gear as 2.66( the standard low gear) x 3.75. The 360,any 360 will have no trouble pulling the other ratios in a 1st gen chassis.The teener, if built right will pull them too. The 273 will be fine in first, but will notice the taller 2nd for sure.It may like the 3.55s better.
If you go this route (long-tail 4speed), you will have to cut your floor up some. So,you guessed it,I would highly recommend that you put the shifter where you want it, and fab up the bracket and rods as required. The rearward mounting makes the 2-3 shift;lightning.It's easy and kinda fun and can be done in a day, without too many special tools.Of course if you have a bench seat and plan to keep it, then you are kinda married to the stock location.
 
AJ/FormS said:
The early models 4-speeds had ratios of 3.09-1.92-1.40-1.00. The 1-2 split is a bit wide, but allows a 14% reduction in rear gear for the same first gear giddy-up. This means you don't have to run 4.10, but rather 4.1 less 14% equals 3.55;surprise! Unfortunately IIRC this 3.09low gear set did not make it into the slip-yoke tranny, which means you will need the later mainshaft and it's tail house, and will have to do a bit of swapping.I have done this swap and can testify that the 3.09 gear will/does work very well with 3.55s. In your Lightweight gen1 car I would recommend 3.23s as being sufficient to launch a streeter with authority, and the extra gear will make hiway cruising much more bearable. The 3.09 x 3.23 = the same starter gear as 2.66( the standard low gear) x 3.75. The 360,any 360 will have no trouble pulling the other ratios in a 1st gen chassis.The teener, if built right will pull them too. The 273 will be fine in first, but will notice the taller 2nd for sure.It may like the 3.55s better.
If you go this route (long-tail 4speed), you will have to cut your floor up some. So,you guessed it,I would highly recommend that you put the shifter where you want it, and fab up the bracket and rods as required. The rearward mounting makes the 2-3 shift;lightning.It's easy and kinda fun and can be done in a day, without too many special tools.Of course if you have a bench seat and plan to keep it, then you are kinda married to the stock location.
Click to expand...
Now give us the long version ? LOL
 
I have 3 kids. The middle child is a daughter. There is a running joke in the family, about her. When she launches into a story, you better sit down.
You think my posts are long? Hah.
I always post the short versions

The E-body shifter mount falls well behind the crossmember in a 2nd gen A. I'll guess about 4 or 5 inches behind the A shifter mount.
The B-body shifter mount falls right in the crossmember and is unuseable, and some of the pad has to be shaved to fit the tailhouse in there.
The trans mounts are the same on all A833s

jpar;I seem to have long legs. The seats never seem to go back far enough. Don't say a word about my fat a$$......heehee
 
Thanks for the great info , I got an homemade adapter from another member . I hope it works , I will have to get some drive shaft work with the slip yoke change. (its a newer 1970 b 4 speed), and it is going to have a 323 sure grip in it. Thanks to another member lol. I'm leaning towards a 318LA+ magnum head combo for power.
 
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