T904 Overdrive Worth the Bother?

[318 Six Pack]

Recalling some old article in MOPAR Muscle or similar, there is an overdrive mod that can be made to T904s and 727s. Anybody have one and are they worth the bother?

My '72 Charger has the original 904 in right now, I have a 727 I could swap with it too. Right now the plan is to just beef up the 904 when I redo the engine. If the OD is worth the trouble, I might as well start saving my nickels for that too.

 

[Relax360]

Gear Vendors makes an OD unit for both. I have one on the back of my 727 really helps the 4.11 gears on the highway.

 

[HorryMorry]

I just put the GV unit in as well and would like to post a word of caution: When they say that it will only require a "small dimple" to clear the tunnel they really mean your tunnel needs to be "Opened up considerably around the unit". I think mine had to be pushed up 1-2" for the length of the OD's round section.

Keep in mind this is really no big deal, I'm still happy I did it, just a heads up that you may want to test fit before putting in your interior.

 

[rumblefish360]

GV's OD tans is expensive.
I myself would rather a A-500 (904 w/OD) or a GM OD trans swap. (Less trans tunnel clearance issues.

 

[rebootej]

A put an 1994 A518 46RH in my 74 satellite, took some effort, a little tunnel modification and had also had to modify the crossmember bracket but really happy with it so far. Havent put any miles on it as the car is getting body work but soon hopefully get it dialed in. It has a better OD ratio than the gear vendor as well.