BB Auto Tranny Question

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mrtires24

mrtires24

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Just wondering what tranny I can use for my demon. I am thinking of doing a low cost buld, and I have a free BB motorhome in the back yard, I just need to pull the engine and tranny.

SO my Question is, can I use that tranny out of the motorhome? I would think it would be too long. Maybe something out of a C body? I know that there will have to be some mods to make an auto fit. Just wondering if the motor home one would work, and if not, what will?

If the tranny won't work, I have complete SB running gear that will go in it.

Thanks

Phil
 
Most of the 727 trannies were the "standard" legnth that came in cars. Some of the truck trannies were actually shorter then the car versions. The long tail trannies were the most common. Visually compare it w/ your small block trans.
 
I used the transmission from a new yorker I didnt have to modify the tranny well at all but I didn't use a truck tranny I don't think they're any diffrent as far as case size just in length
 
I've got a '74 motorhome 727 in my car. It's the exact same as a car transmission. No mods at all to get it in.
 
wish4hemi said:
I've got a '74 motorhome 727 in my car. It's the exact same as a car transmission. No mods at all to get it in.
Click to expand...

Was it out of a BIG motorhome? The one I have is Big.

Also, How much did you have to alter the drive shaft? Length?

I thought that with auto trannies you had to modifie the tranny mount. Guess I was wrong.

This could be easier than i thought for the swap. I guess the exhaust manifolds won't work though. DO I need ones from a C body?

Phil
 
mrtires24 said:
Was it out of a BIG motorhome? The one I have is Big.

Also, How much did you have to alter the drive shaft? Length?

I thought that with auto trannies you had to modifie the tranny mount. Guess I was wrong.

This could be easier than i thought for the swap. I guess the exhaust manifolds won't work though. DO I need ones from a C body?

Phil
Click to expand...

Yes, it was out of a big motorhome, not one of the truck/van things with a camper in the bed. It was a direct fit and looks exactly like all of my A/B/E 727's. Same driveshaft was used too. Motorhome exhaust manifolds are center dump and will not work. Not sure about the C-body manifolds, but here is a link on how to use B-body manifolds in an A-body: http://www.bigblockdart.com/techpages/HPman.shtml The only 727 that I have ever seen that is different is the truck 4x4 727 which is shorter and has an adapter on the back to go to the transfer case instead of the long tailshaft.
 
wish4hemi said:
Yes, it was out of a big motorhome, not one of the truck/van things with a camper in the bed. It was a direct fit and looks exactly like all of my A/B/E 727's. Same driveshaft was used too. Motorhome exhaust manifolds are center dump and will not work. Not sure about the C-body manifolds, but here is a link on how to use B-body manifolds in an A-body: http://www.bigblockdart.com/techpages/HPman.shtml The only 727 that I have ever seen that is different is the truck 4x4 727 which is shorter and has an adapter on the back to go to the transfer case instead of the long tailshaft.
Click to expand...


Hmm, This is very interesting.

Do some motor plate, Clean up the engine/tranny. get an oil pan, and I could have a driving BB demon.

This could be interesting.

Hey WIsh4hemi, Is it ok if I PM you when I get my engine/tranny out and compare measurmints? won't be for a little bit.

Thanks

Phil
 
Yeah, you can PM me. The transmission should be 35 inches in overall length.
 
The main reason ya go to a shorter drive shaft is if you change from a 8 1/4" or 7 1/4" and got to a 8 3/4".
 
You will want to make sure it doesnt have the parking brake assembly on the tail shaft, and that the tail shaft is not the HD unit found on some trucks. The brake is a big drum on the tail of the trans... If you have it, the mainshaft and tailhousing need to be changed. The HD truck one has the access hole for the retainind snap ring on the side of the housing and it may hit the floor on A bodies. I know the one I tried did. That one you only need to change the tail housing with a passeger car one and you're fine.
 
moper said:
You will want to make sure it doesnt have the parking brake assembly on the tail shaft, and that the tail shaft is not the HD unit found on some trucks. The brake is a big drum on the tail of the trans... If you have it, the mainshaft and tailhousing need to be changed. The HD truck one has the access hole for the retainind snap ring on the side of the housing and it may hit the floor on A bodies. I know the one I tried did. That one you only need to change the tail housing with a passeger car one and you're fine.
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I agree on this accept it would be the output shaft that would have to be changed and the tail housing, but not a big deal to do if you had the parts.
 
I took a closer look at the engine today, It does not have the flat area where you would see 440 stamped on it. I was wondering if anyone know how I can tell what the engine is? I know that it will say on the left side of the block, but I can't get under the motorhome right now.

here is the Vin if it will help...
F44CJ8V701***

I have done a couple vin decoders, and it comes back as a hemi! I wish.

Phil
 
There is a pad below the distributor and right above the water pump that should have the displacement stamped on it for B-blocks. I would guess it is a 400.
 
wish4hemi said:
There is a pad below the distributor and right above the water pump that should have the displacement stamped on it for B-blocks. I would guess it is a 400.
Click to expand...

I think this is the same pad that is on my car, but not the motor home...bOn my car's 440 it is more to the center drivers side of the front of the engine, above the water pump.

Same pad, you are talking about, or different?

Phil
 
mrtires24 said:
I think this is the same pad that is on my car, but not the motor home...bOn my car's 440 it is more to the center drivers side of the front of the engine, above the water pump.

Same pad, you are talking about, or different?

Phil
Click to expand...

The pad for B-blocks is in a different spot (circled in yellow).

383.jpg
 
The displacement is cast into the passenger side of the block near the freeze plugs.
 
70Duster440 said:
The displacement is cast into the passenger side of the block near the freeze plugs.
Click to expand...
I thought it was the drivers side...oops, I'll have to look again.

I will also have to look for the other pad.

Thanks for your help guys.

Sold the demon anyways. It wasn't for sale, but someone else has it that will do some good work to it.

Phil
 
It's a 400,

Kinda sucks, I was hoping for a 440. don't know if I'm going to waste my time with it.

Not sure yet.

Hmmm

Phil
 
400s seem to be the block of choice now days due to the larger bore and heavier block casting id take if i could have it, your tranny may have a bolt on yoke on the tranny and will require a tail shaft and tail housing swap.
 
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