r7 od question

[40plyrod]

Hi Sorry about another overdrive question. The 40 plymouth sedan I'm building has the original overdrive and looks to be complete but I haven't taken anything apart yet to see what it looks like inside( I'm still patching rust so my friends stop joking about needing a tetnus shot just to come near it!) I'm just gathering information about the overdrive on how it drives I've never driven it or rode it one. I've searched around this forum and the web and the things I read say that the r7 is simple(sounds good to me) but fussey and not very user friendly(not good) I'm just wondering what makes them fussey? Are they harder to shift? I know that I'm gonna keep the flathead but just trying to decide if I should start looking for a different transmission. Thanks

[greg g]

The r7 was a similar unit but lacked the kickdown circuitry. Relying on the governor to engage and disengage the unit. So it was basiclly a top gear over 25 mph deal. If the cable was in the on position, a let off of the gaspedal over the cut in speed would shift into OD. If you needed to drop out for passing or running up hill, you would need to disengage manually ar wait till you slowed below the cut in speed (which was about 25mph)

here is some info, basically on the later uits but some mention of the earlier one

http://www.dacoglu.com/desotoCD/11A_ThreeSpeed%20With%20Overdrive/Borg%20Warner%20Overdrive%20Transmission.doc

[james curl]

You could still shift down to second above the governor drop out speed, it would just be in 2nd overdrive. I have the R-10 overdrive in my 55 Chevy pick up. I have a toggle switch that activates a relay to get power to the solenoid. I do not have my governor wired into the solenoid circuit. I can run in overdrive in all three gears when the switch is in the on position, if I want to split shift or drop out of overdrive I flip the switch off and let off of the gas until the overdrive drops out, about 15 seconds at most. As long as I have the cable pushed in, which is always the truck freewheels when you let off of the gas pedal. You have to put it in reverse after you park when the switch is off or it will roll away unless the emergency brake is applied.

[claybill]

ha! just listening to 'overdrive talk' makes me nervous. i had an r-10 in my 41 and just plain took it out and sold it! it still runs fine at 55.

bill

[40plyrod]

Thanks for the file greg. So if I understand this right and the kick down circuitry is the main difference between the r7 and the r10 can the governor be removed and a kick down circuit be added to the r7?