I need to get a big block 727 to put behind a big block stroker motor (approx. 600 hp street driven car). Is there any particular year or range of years of 727's that are better than others for this application? Should I look for an original 383-4 hp or 440-4 hp trans. or would a non-hp trans. suffice? A friend of mine has a 727 from a 1972 440 C-body that I can get if need be otherwise I will look for whatever is recommended.

I was told years ago(mid 1980s) that the 1966 B body trannys had the best cases to use for drag racing by Dave Smith at Pro Trans.
I'm not sure what year Mopar started adding the 4 pinion planetary in the motor homes and H.D tranny for pickups and Vans
600 HP is not a lot for most 727 with good parts in them
I use to build my own drag racing 727 and then figure out is was better for me to Have Dave at Pro Trans build mine form then on
I've had tranny built by A1,Art Carr and several other SO CA drag race tranny companies before switching to Pro Trans. I recommend you contact them
Their located in mid Texas now so shipping is faster and sometimes cheaper than when they where in SO CA
Their are somethings I want done for me by the best in the business like brain surgery, race trannys and several other things I won't bore you with on here now

T

That 72 would be a good choice for a couple reasons.

Being it’s from a land yacht it likely never got abused.
The internals are probably like brand new inside.
Also, it has the later pump/reaction shaft support/wide front clutch bushing. A 3 pinion front carrier is the carrier of choice, not a 4 pinion.

Check the front drum, if it has only 3 frictions you can easily modify the pressure plate in that drum to accept 4 discs.
I assume you will be using an aftermarket valve body, the rest of the components in the transmission are fine for your power level.
I would install a bolt in over running clutch.

Get the right parts and valve body and for a street car, even a stroked street car, you'll be fine. Especially if you plan on running street tires.With street tires you'll never load a well built 727 enough to hurt it. It won't be scared of drag radials either, cause they won't dead hook on the street either with a hot stroker. It would take a lot of torque, stall, and traction to even start to threaten the integrity of a well built 727, no matter the cores humble beginnings.

I have had both 3 and 4 pinion planetary 727s behind my strokers on the street and strip with drag radials for many years and have never hurt a planetary. The best advice above is to go with the core you can find with the least abuse. That is probably more important than the number of gears, at least in my opinion and experience.

P.S. Where are you located? I have a dozen or more good BB 727 cores that I will never use. Some from passenger cars and some from trucks/,motor homes.

I agree with above. I have never hurt or broke anything major in a 727 in any of my cars.

Just started counting up what I have laying around and I have 9 spares myself from a couple cable shift, to several linkage shift and motohome transmission's also.

I have a transmission from a 66 B-body I’m going to rebuild. I’ve read something about the input shaft being smaller or having less splines, requiring the use of the earlier torque converter?? Did it change in ‘67? I’m not sure can someone shed some light on this??

67 and later used a larger input shaft journal that rides in the small bushing of the reaction shaft support, and yes the splines changed for the converter.

Keep the pump and input shaft matched and you will avoid a lot of strange issues that happen when you put small shafts in large supports. It gets stickier in 1971.

I would add that whatever you decide remember these transmissions are as much 55 years old with the newest ones being about 35 years old.

There is no telling how many miles are on whatever you buy. Do not be afraid to buy new billet hubs, bolt in sprags, and such just for the piece of mind.

Even if you are not going to build a 1500 HP monster motor it may save you from a breakdown.

My

Generally speaking, mileage is not an indicator of remaining useful life in a transmission.

Operating cycles at high power levels are.

A drag car puts on a 1/4 mile at a time and cycles the parts causing more loading than driving a car 100’s of thousands of miles.

And in high gear the geartrain sees no wear and tear.
Just bushings in the pump and front clutch drum, rotors, and the output shaft bearing.

Again, a seasoned C Body trans would be my first choice for a core.

All 727 trans main cases are the same dimensionally, none are better than others. The only thing you may observe on cases is that some have additional external webbing and that is usually for truck applications for off-road and 4 x 4 use.
Not for torsional issues but for vibration and cracking due to severe jarring.

Use the '72. The '71 and up used the pump that accepts the wide bushing front drum. I think all the aftermarket drums use the wide bushing.
A heavy duty 727 will have a 4-clutch front drum vs, the 3-clutch, but for safety, a billet drum is recommended and will fit 5-clutches like the Hemi version.
If you have a 3-clutch front drum, and just want a standard 4-clutch drum, it is just a simple swap of parts. A&A lists a reconditioned 4-clutch drum for $75.
The 5-clutch front drum requires the rear drum to be beveled for clearance, or use an aftermarket billet rear drum too.
Don't worry about the number of pinions the front planetary uses, the aluminum splines are the week point. If you have the power to hurt the aluminum splines, then you need an aftermarket steel planetary.
The Trans-Go TF-2 shift kit to reprogram the valve body if you want to maintain the automatic shifting and will need the kickdown linkage. A Manual Reverse valve body is an option, and don't need the kickdown linkage, but need a shifter that works with the reverse manual valve body.
If the front band lever is a 3.8:1 ratio (Ratio is stamped in the lever) then use it, otherwise use a 4.2:1 ratio. I think Cope Racing Transmissions have them for about $25, but it;s been several years since I checked prices.
The standard for racing clutches are the Alto Red Eagle with the Koleen treated steel plates.

Anyhow, skipping to the end, if the stock '72 is in good condition just do the TF-2 shift kit and run it till it starts slipping, Then inspect it and rebuild/upgrade as needed.

The '66 should have 19-spline input shaft unless it was converted.
To convert to the later 23-spline you need the inputshaft and matching front pump (and maybe the front drum too if '71+) from a later model vehicle.

When changing pumps, drums and such, you need to verify the input shaft endplay (really a good idea even if re-using the original parts.)
The endplay is adjusted with different thickness washers on the pump.

Hey Transman, didn’t some 47 or 48 series of trannys have steel planetaries? I hung onto a couple for that reason. Jim.