727 Trans. Lengths Short/Long?

[ArtfulDodger]

I was reading where nfury8 had both short and long 727's in the shop.
Can someone explain the difference in length, and where they were used. Perhaps what years I should look for.
I have an extended block 331 hemi, and I have bought a Wilcap adapter to a 727 small block bolt pattern.
I want to keep things as short as possible, so was wondering what the difference in tranny was.
What type of connection to the driveshaft will I have? Bolt up or slip on?
This will be going into my 53 New Yorker Coupe.
Say goodbye to semi auto startups in 3rd gear.
Thanks for any info.

[Russ]

The short tailshaft 727s came in trucks and have a bolt up flange on the output shaft. I think that the long tailshaft models are about six inches longer and have a slip yoke to the driveshaft. The mounting pads are in the same relative position and a short shaft tranny will bolt right in where a long shaft tranny was, so you might not need to be concerned about the difference if mounting it is your concern. The long shaft ones are much easier and usually cheaper to obtain. You are going to loose your emergency brake though unless you change to a later rear end also.

[ArtfulDodger]

Thanks Russ for the info.
I think I like the short one. If it is a truck item, maybe it's a bit more heavy duty. The car weighs over 4000lbs.
The old semi auto tranny is really just an electrically shifted 4 speed manual. It has a bolt up flange on the tailshaft.
Changing the diff is in the plan both to get back a parking brake, and get rid of the left /right studs.
Have not done any measuring for that yet.
I want to get rid of the studs on the front as well, but I want to go to discs at the same time.
I have heard there is an outfit that will machine my spindles and fit them with a disc kit.
Need to check that out.
I'm not in a hurry, just a bit at a time.

[nfury8]

The short tail 727s were used exclusively with 4x4 trucks and divorced transfer cases.
I believe they are standard 727's with just short tail housings and shafts. Seems like
the housings can be swapped, but the trans has to come apart to do it.

[ArtfulDodger]

Thanks for your info Nfury8;
Likely have to adapt to exising tranny crossmember anyway, so the long tailshaft slip joint is less $$ and easier to come by.
Was hoping that I wouldn't have to carve up the floor hump by using a shorter tranny.
A friend is telling me about a 318 Diplomat. Says that I could get that tranny with mount, and even swap out the front end to get modern discs, and power steering.
Are these 904's, or 727's?
On that line,I wonder if a Cordoba would give all that and a rear end?
I heard something about transverse and longitudinal torsion bars.
Have to get out the tape.

[Russ]

Thanks for your info Nfury8;
Likely have to adapt to exising tranny crossmember anyway, so the long tailshaft slip joint is less $$ and easier to come by.
Was hoping that I wouldn't have to carve up the floor hump by using a shorter tranny.
A friend is telling me about a 318 Diplomat. Says that I could get that tranny with mount, and even swap out the front end to get modern discs, and power steering.
Are these 904's, or 727's?
On that line,I wonder if a Cordoba would give all that and a rear end?
I heard something about transverse and longitudinal torsion bars.
Have to get out the tape.

If the Diplomat wasn't a police car it will have a 904 with a lock up converter. I'm not sure if a police car would have a 727 or not. The lock up converter will help your gas mileage slightly but my experience with them has been that they are not as durable as a 727, or even a non-lockup 904. The Cordoba has pretty much the same mechanicals and suspension as the Diplomat.

[ArtfulDodger]

Thanks Russ;
I think I'll pass on the diplomat. The Wilcap aluminum adapter plate is designed to be used on a 727.

[nfury8]

Small block 727s are going to be scarce in cars, and cars will use a totally different mount.

[Russ]

I'm going from memory here, but I don't think the transmission rear housing bolt holes changed when they switched to the round mount. The bracket for the newer style mount bolts into the same holes as the older style flat mount.