[WANTED] Overdrive for big block

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I am looking for an overdrive unit to put in my big bock Dart. It currently has a 3 speed 727. I am either looking for a Vendor overdrive unit to pair with my 727 or a later model auto overdrive trans and or possibly a manual shift overdrive transmission.
 
Roy, you do
I am looking for an overdrive unit to put in my big bock Dart. It currently has a 3 speed 727. I am either looking for a Vendor overdrive unit to pair with my 727 or a later model auto overdrive trans and or possibly a manual shift overdrive transmission.
realize that a factory OD trans in a manual for a BB was not available and the use of the factory manual OD will require a aftermarket bell housing or replacing the bearing retainer for a smaller one to use with a OEM bell housing?

There was also never a factory automatic OD transmission for BB engines. Making use of one would require a Reed bell housing which has the OEM trans bell housing removed.
 
Yes I have done some research on this in the past and I am aware of the bell housing issue. I am hoping that maybe a member might be able to assist me with what I need
 
Roy, you do

realize that a factory OD trans in a manual for a BB was not available and the use of the factory manual OD will require a aftermarket bell housing or replacing the bearing retainer for a smaller one to use with a OEM bell housing?

There was also never a factory automatic OD transmission for BB engines. Making use of one would require a Reed bell housing which has the OEM trans bell housing removed.
Never heard of them, but will check them out. Thanks!
EDIT Reid does not have anything for big block Mopar

OR that 850.00 adapter kit sold by A&A trans.

Yeah and I think on most you're either amputating the ear on the block or hogging out the bell housing.

There was a guy in Tennessee making these adapters, too, and he had a pile of them in his shop, but last time I was by the building was locked and he was old enough I figure he just kicked off.
 
The 440 in my station wagon had a 518 installed with one of the kits. Here are 2 pics of the block ear below the starter. It has to be amputated. I added mid mount brackets to the frame and just made a spacer to attach to the trans bellhousing.

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A833OD for a big block requires:

A new aluminum bellhousing with the 4.8 hole.
On the OD turn down the bearing retainer from 5.125 to 4.8.
Hurst a-body shifter, new OD rods and levers (can also use any a-body shifter with 1/2 and reverse rods/levers, except must use the OD 3/4 rod/lever.

Note: 4.35 is too small for the A833OD bolt circle.
 
Gill Welding is also supposedly working on something to work for this.
 
I installed an 85 OD833 in my GTX last year; it was trivial to install. I had a new bellhousing from Brewers (because I sold my old one like a moron) and just changed out the front bearing retainer, also from Brewers. Shifter and rods were the same ones I had used for years with a standard 833 and just flipped the dog at the required location.

I'm going to run the wheels off it and see how long it lasts.

Oh and just a shout out to the Brewers guys; Been buying odds and ends from them for years, exceptional service every single time. The bellhousing that I purchased had exceptional machine work.

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Yes! Brewers has the correct bearing retainer, forgot about that.

I tried to flip/use the original 3/4 rod when I swapped in the OD, doesn't work on an a-body, at least on mine it didn't.
Interferes with both the 1/2 and crossmember, iirc.

Nice to know on a b-body the standard 3/4 rod can be used.
 
Yes! Brewers has the correct bearing retainer, forgot about that.

I tried to flip/use the original 3/4 rod when I swapped in the OD, doesn't work on an a-body, at least on mine it didn't.
Interferes with both the 1/2 and crossmember, iirc.

Nice to know on a b-body the standard 3/4 rod can be used.
Failure on my part to mention, my 1970 is using the 1971+ B/E pad location. Someone installed a 4-speed in the car a very long time ago and when they did they used a B/E unit.

So on the shorter A body or B body rod applications, your mileage may vary. A-bodies did come with the OD transmissions so it should be trivial to find the parts or make something work.

I had a few over the years including a real Feather Duster slant six-OD833 combo.

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Last time you said that I called them. They said No Bueno
They have one of the old adapter plates that used a big block 727 behind a slant 6 and said they were going to work on that, as well as what's needed here. I think David and Bryce are the only two that run that shop so they probably stay pretty wrapped up. I hope.
 
Pretty easy to run a OEM manual O/D in an A-Body. I swap an early cast iron (307 main bearing) main housing and counter shaft for the aluminum O/D main housing and O/D counter shaft and use the rest from an A or F body O/D. For a big block I'd run a 30 spline main shaft. That way you can run an original big block bell housing. Or if buying a new bell housing from Brewers, just get one for the 4.807 front bearing retainer and swap front bearing retainers (they use the same 4.16 bolt circle). Either way, I ditch the aluminum main housing. slop, or "float" is not a good thing in a gear box. Then the rest is "just" a manual trans swap.
 
Pretty easy to run a OEM manual O/D in an A-Body. I swap an early cast iron (307 main bearing) main housing and counter shaft for the aluminum O/D main housing and O/D counter shaft and use the rest from an A or F body O/D. For a big block I'd run a 30 spline main shaft. That way you can run an original big block bell housing. Or if buying a new bell housing from Brewers, just get one for the 4.807 front bearing retainer and swap front bearing retainers (they use the same 4.16 bolt circle). Either way, I ditch the aluminum main housing. slop, or "float" is not a good thing in a gear box. Then the rest is "just" a manual trans swap.
I've seen some of the forum gurus ***** about "how bad" the ratios are in the 833 OD. I've run three or four in different things and I found they're fine. As long as you don't have something that won't pull a greasy string outta a cat's butt and you know how to drive, you're good.
 
I've seen some of the forum gurus ***** about "how bad" the ratios are in the 833 OD. I've run three or four in different things and I found they're fine. As long as you don't have something that won't pull a greasy string outta a cat's butt and you know how to drive, you're good.
Yeah, I have to laugh since I run a 273. Been running one since the 80's. For a while it was behind a hopped up 170 /6. No problems with either engine.
 

I put together a big block 518 a few years ago. I haven’t put it in anything yet. Used a J and W 727 bell that bolts to the pump bolts. I thought this setup would be better than an adapter and sawing off part of the block, but either will work fine in an A body after you mod the crossmember and all that jazz.
 
Used a J and W 727 bell that bolts to the pump bolts. I thought this setup would be better than an adapter and sawing off part of the block,
That requires the bell housing of the transmission to be cut off and machined, correct?
 
I am i
I put together a big block 518 a few years ago. I haven’t put it in anything yet. Used a J and W 727 bell that bolts to the pump bolts. I thought this setup would be better than an adapter and sawing off part of the block, but either will work fine in an A body after you mod the crossmember and all that jazz.
 
My D-100 has a 1969 440 and an 833 OD with an iron bell housing.

Not sure how they did it, but it works.

I have documented that both the "extra" 833 OD transmissions I have, have bearing retainers that would place the retainer bolts partially inside the bell housing, if the retainer hole is machined to accept the factory retainer. Also, this could interfere with the shift fork mount, depend on which fork and mount you have.

-Make sure everything matches up, and then make sure a second time.
 
My D-100 has a 1969 440 and an 833 OD with an iron bell housing.
OP has Automatic
I am looking for an overdrive unit to put in my big bock Dart. It currently has a 3 speed 727. I am either looking for a Vendor overdrive unit to pair with my 727 or a later model auto overdrive trans and or possibly a manual shift overdrive transmission.
His last line is slightly confusing but I interpreted it to mean an automatic OD that can be turned on and of at will not electronically controlled by an ECU or the transmission
 
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