Gear Vendors OD on a 73’ Javelin

Trader wrote: The GV 727 AMC does not have the program module that I know of. An electronic controlled transmission can use the GV program module. Apples and oranges. If GV or aftermarket now has an electronic control module for a TV cable transmission, please post the site. I'd certainly be interested in reading the specs and installation.

I did not know about the speed control not working with non computer cars.

Though back 2004 when I made the decision to go with a GV, there was marketing stating it would work.

Here is a link from a site that I searched for 'gearvendors shift module th400' https://www.drivetrain.com/parts-catalog/overdrive-units/gear-vendors-chevy-a-gm-3-speed-automatic-trans

Trader wrote: Before putting down big $$$, call GV and ensure the electronic control unit will work with an AMC 727. The TH400 is a different transmission and the Chrysler 727 has a different tail housing as far as I remember from the AMC 727. The GV electronic control requires it to work with the tail housing governor on the Chrysler 727. I don't see one specifically for the AMC 727, though they may be the same bolt on unit. Just check before writing the cheque. Would be good if you could post the response from GV for the Forum.

Ah, sorry I gave GM info... not thinking you were concerned about governor control. As far as I know the new GV units and controller don't use governors to control shift.

Some where in the info I read the controller reads data around 1000 times per second. I think the module hooks up to their speedo adapter with signal processing, engime vacuum port, to adjust down shift and upshift by RPM change. Taking samples and comparing them constantly. It's a pretty trick module, unlike a relay and switches. Can be programmed by the user for shift speeds, unlike just OD control.

Since it uses a computer it adjusts for small variations before sending a signal to the GV unit.

If you look carefully there is no electronic parts other than wires, speedo housing with special signal adapter, and control module. No governor swap. The speedo hole is plugged, and relocated using their speedo kit with a proper gearing for reading speeds from the gear vender output shaft.

The same stuFF is used on GM, just a different tail end adapter and speedo housing for GM fitment.

Here is the links from gearvendors site. A bit more clear on pictures but details are the same for both GM and Dodge TQ which is the same for AMC



https://www.gearvendors.com/hrdodge3s.html

Edited by 304-dude - Oct/31/2020 at 3:48am

Ok, so everyone seems concerned that the AMC tail shaft is different than Dodge. Since AMC th400 accepts a GM bolt patern tail shaft end, why would the AMC TC727 not be able to fit a TF727 tail shaft end? The only difference would be the tranny crossmember mounting pad location. It seems the easiest change to do to place the tranny in an amc, than to redesign to fit. If an amc tail shaft end is the same length as a Dodge, then that would make my theory correct. I just don't see AMC spending money on retooling already ready available tranny parts, when they have been careful bean counters since the 1970.

Mopar_guy wrote: FWIW, the tail housing won't even be used. GV has their own housing that will bolt to the main case. There are are 3 main lengths of 727 tail shafts. An 8",12" and the most common 18". Dave is changing his to an 8" so that with the GV unit, it won't be much longer than what the length is now.

That's what I thought... just the info sounded like the tail housing was different in bolting on to a tc727 than mopar. Which I doubted, but had question. Thanks for clearing this matter up for the members who questioned. It's pretty much like the jeep th400 case, just swap out output shaft and bolt on the adapter for the GV unit.

Basically the Mopar GV unit should work just fine on AMC. In a way it was better for people interested in such units to have waited after 2004, like me. Major improvements, and the nicely setup controller.

All,

Edited by DMack - Jun/30/2022 at 3:26pm