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from 3 speed auto to overdrive

ord27

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Is there a transmission that has an overdrive that's a complete swap kit?
1970 Coronet
 
You can add a Gear Vendor unit on. You do have other options. Do you have BB or SB?
 
TCI takes a pumped up 4L80, chops off bell housing and bolts a Reid aluminum one on that has Mopar BB bolt pattern. Good to 800 Ft/pounds and has 6 speeds. Have one in my 69 Coronet and finishing up the total wiring overhaul now.
 
Silver Sport Transmissions specializes in complete kits to install a mopar automatic overdrive a41 in place of the 727
 
like that 6 speed
also bb to sb adapter and use 92-95 518 46rH 3 pin connector
if rebuilding you can put 47re guts in it
I have the early trans diesielized with the straight cut gears and more plates etc
but shaft size gets bigger so the later trans uses 15 degree planatries- they do NOT interchange
let us know what you come up with
I would think plan on some simple crossmember and tin work no matter what- driveshaft shorten etc
 
mine is a base model 318 with a 2 barrel carb. I built it for my daughter for her college graduation gift. She loves it, but the thing drinks gas.
I took the small real axle , that had some tall gears in it, and swapped it for an 8 3/4 posi unit that houses 3:73 or something close.
My original thought was to build it for resale, but she claimed it.
Now I need to make it more economical. I might eventually put taller gears back in it
thanks for the input !
 
early 518 no question about it
you could even run the A500 42 rh
the od unit is the same so you can go t 9-10 clutches
use the Transgo spring and reprogramming kit and new vb seperator plate
weak spot is the thrust plates so big oil cooler and not the early 30 ish degree helical planataries
you can rebuild the front end with 999 parts but it is ok
but from v6 v8's got the 518
 
mine is a base model 318 with a 2 barrel carb. I built it for my daughter for her college graduation gift. She loves it, but the thing drinks gas.
I took the small real axle , that had some tall gears in it, and swapped it for an 8 3/4 posi unit that houses 3:73 or something close.
My original thought was to build it for resale, but she claimed it.
Now I need to make it more economical. I might eventually put taller gears back in it
thanks for the input !
You have to consider that if you spend a few hundred dollars on the change, will you ever get that much back in gas savings?
 
gas mileage is one thing enjoyable to live with is the big reason to PD
 
TCI takes a pumped up 4L80, chops off bell housing and bolts a Reid aluminum one on that has Mopar BB bolt pattern. Good to 800 Ft/pounds and has 6 speeds. Have one in my 69 Coronet and finishing up the total wiring overhaul now.
TCI makes a conversion kit that comes with an adaptor plate as well as a toothed flex plate to convert to a GM OD trans... I bought a couple of them at the swap meet cheap... I will have to buy the right flex plate as they are 8 hole..
The only thing holding me back is I just installed a new floor pan and am not sure if I want to cut it to fit a 4l80/700 or just deal with it until I can save up for a GV unit...
 
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Mike67....The floor pan and hump DEFINATELY needs to be modified when you swap the GM for the Ried bell housing on the full swap from them! I am hoping all this extra work will be worth it when I finally get her on the road. I posted a pic of the modified hump I did to make it work...still have to wrap carpet around this TOO.
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