66-67 Dodge Charger Source Guide

Transmission Q & A

Mike: What I trying to find is a 4.2 shift lever for the 727 trans. I can find the 5.1 lever but not the 4.2 I'm not sure what the difference is but a friend of mine who owns a trans shop say that the lever I should get is the 4.2 If I can't find it the 5.1 is better than what's in the trans now. Also if someone could tell me what the difference is between the 2 levers and how they each make the trans shift it would be appreciated.

Charger Andy: That lever is what applies the force on the band that grabs the front drum in the auto trans. The higher that number (the ratio at which it multplies the force) the tighter the band will grip the drum. The 5.1 will give a rock solid engagement, but it will react to the band's wearing down faster. You will need to do a front band adjustment on the trans about twice as often as with the 4.2 arm. This adjustment is external and not really a big deal. I went with the 4.2 arm in my tranny and was quite pleased with the added performance over the old 2.9 that was in it.
I had bought my 4.2 arm at the dealeship about 4 years ago. Right after that it seems the supply dried up. You'll have to try around some Mopar prformace suppliers. Give Mancini a shout. They really helped me find some good tranny parts for my buildup, like that forged steel kevlar-lined front band you should use with the new lever.