Big Block 727,s created equal?

BigCRig

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My understanding that the later 727's 71 and newer,[wider clutch bushing]are a better trans than the earlier 727, and the lockup converter came around 78, also I know converters and trans,need to be year specific,not all converters will work with all trannys. I think you can use a 727 out of a motorhome, you have to change the tailshaft and housing. Also I have heard that the 727 that backed up the 440's has 1 extra clutch band. Now I am no expert on transmissions probably know enough to get into trouble,and I also realize I'm throwing a lot out there, but my question is this... I have a 69 440 H.P. and the trans that I have is #2538334 which is 66-68 383., the motor will be built pretty much stock with a moderate cam performer intake,and 4 bbl. hopefully I can get close to 500 h.p. or am I too optimistic. Now would any of you have reservations putting this trans behind this motor. Oh it's going in my 66 Sport Fury. Thanks in advance.
 
That trans would likely be fine and if it needs rebuilding you can find yourself a doner mid '90s 46 RE and swap some greatly improved parts from it into your 727.
 
That trans would likely be fine and if it needs rebuilding you can find yourself a doner mid '90s 46 RE and swap some greatly improved parts from it into your 727.

I am confused. I'm not big in transmissions innards, but the 46RE has overdrive right? What can we use from these?
 
The 46 and 518 transmission is based on the 727 directly. Here's what I had done to the trans in my '71 Challenger 383.

Transmission accomplished!
image-jpeg.74506

Here are the highlights
Here are a few of the improvements made to my trans. I found a used late '90s 46RE on Craigslist as a doner for some of the mods. The valve body got a shift improver kit and the oem steel check balls were replaced with the composite ones from the 46RE as they don't beat up the separator plate like the steel ones.
New TCI HP intermediate sprags.
New style dimpled input bushing in pump housing for improved oiling.
Replaced main output shaft bearing.
Back planetary set was replaced from the oem 3 gear set to the 4 gear from the 46RE.
Front clutch pack springs went from the 9 originals + 3 reds from the 46RE to = 12.
Front clutch pack bushing replaced with new updated grooved style for improved oiling.
Front clutch pack discs changed from 4 oem to 5 Alto-red .062 discs.
Back clutch pack discs changed from 3 oem to 4 alto-red .062 discs.
Kick down apply lever changed from 3.2 oem to 3.8.
New front and rear bands, good ones.
6 1/2" washers used as blocker in the low/reverse apply piston assembly.
Removed casting flashings from case(one was dangerously close to falling off which would have been disasterous)
This was all done by a close friend of mine whose a guru imo and I'm really looking forward to experiencing the performance of this trans.
 
Wow, so you now have overdrive? Will this setup work also with 65 727? I was planning on having my trans rebuilt anyways.
 
46RH/RE, 47RH/RE, 518/618 dont bolt to big blocks. Those are small block transmissions.
But i think internals can be swapped around with 727.
If want 518/46/47 into big block u need bell housing from JW Performance UltraBell.
 
No overdrive just additional clutch surface and the extra planetary gear among other things listed there.
 
The 46 and 518 transmission is based on the 727 directly. Here's what I had done to the trans in my '71 Challenger 383.

Transmission accomplished!
image-jpeg.74506

Here are the highlights
Here are a few of the improvements made to my trans. I found a used late '90s 46RE on Craigslist as a doner for some of the mods. The valve body got a shift improver kit and the oem steel check balls were replaced with the composite ones from the 46RE as they don't beat up the separator plate like the steel ones.
New TCI HP intermediate sprags.
New style dimpled input bushing in pump housing for improved oiling.
Replaced main output shaft bearing.
Back planetary set was replaced from the oem 3 gear set to the 4 gear from the 46RE.
Front clutch pack springs went from the 9 originals + 3 reds from the 46RE to = 12.
Front clutch pack bushing replaced with new updated grooved style for improved oiling.
Front clutch pack discs changed from 4 oem to 5 Alto-red .062 discs.
Back clutch pack discs changed from 3 oem to 4 alto-red .062 discs.
Kick down apply lever changed from 3.2 oem to 3.8.
New front and rear bands, good ones.
6 1/2" washers used as blocker in the low/reverse apply piston assembly.
Removed casting flashings from case(one was dangerously close to falling off which would have been disasterous)
This was all done by a close friend of mine whose a guru imo and I'm really looking forward to experiencing the performance of this trans.
Amazing! How folks on this site have pics available,thanks a bunch for the trans upgrade info. and the picture.
 
This is the 46 RE, the pic I posted was my 727. My doner 46 RE came out of a '98ish 2 wd pick up with a V8. I bought it on Craigslist for 100 bucks but it took a while to find a cheap one.

IMG_2229.PNG
 
Picture is 4wd transmission. OD unit is bolt-on swap with 4wd->2wd->4wd.
Also looking for cheap/working 46RH or 47RH with lock-up converter. RH = hydraulic controlled OD unit, RE is computer controlled OD unit and aftermarket control units are 1-2k $..... :mob:
 
All I used from the 46 was innards.
 
My understanding that the later 727's 71 and newer,[wider clutch bushing]are a better trans than the earlier 727, and the lockup converter came around 78, also I know converters and trans,need to be year specific,not all converters will work with all trannys. I think you can use a 727 out of a motorhome, you have to change the tailshaft and housing. Also I have heard that the 727 that backed up the 440's has 1 extra clutch band. Now I am no expert on transmissions probably know enough to get into trouble,and I also realize I'm throwing a lot out there, but my question is this... I have a 69 440 H.P. and the trans that I have is #2538334 which is 66-68 383., the motor will be built pretty much stock with a moderate cam performer intake,and 4 bbl. hopefully I can get close to 500 h.p. or am I too optimistic. Now would any of you have reservations putting this trans behind this motor. Oh it's going in my 66 Sport Fury. Thanks in advance.

66 and earlier have a 19 spline input shaft. 71up have the wider bushing in the pump housing, this pump can be.put into a earlier trans. If you can get rid of 19 spline input shaft I would do it much harder to find a converter for and performance converter is basically non existent. The clutches in a 727 are very good except maybe the later 3 disc forward clutch pack on some out 2bbl engines. The 3 pinion gear sets should be changed in 400 plus horsepower range. The band's and the sprag are the only mediocre pieces for HP, a bolt in sprag and some of the bands developed for the diesels have made that a moot point.
 
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