42RH / A-500 in a Duster with pictures.
Success!!
Just back from the cruise to Burger King on the Berlin Turnpike and the car was great!
The lower first gear set (2.74 vs 2.45) and slightly looser converter have noticeable snap off the line, it bangs through the gears with authority and cruise is simply a joy! The overdrive and lockup have lopped over a 1000 rpm off at cruise, where before I was buzzing the hell out of the motor at 65 mph now it turns a leisurely 2000 rpm while cranking along at 80 mph! For once I was passing everyone on the highway instead of being passed all the time!
The sweet spot is between 75-80 mph, the car is just loafing along, very little pedal is needed to maintain speed and the cabin noise is notably less. Very simple to toggle the overdrive and lockup on and off and compare the changes. I have it wired so that lockup and overdrive comes in at the same time, very simple and works great. The motor doesn't seem to mind the load at all till around 1400 rpm or so. 1500 rpm and up and it just pulls away on the highway & state roads.
Shown in the first picture is one of the plates I made up for the floor pan. It bridges across the top of the trans cross member and ties it into the hoop for a little more rigidity. Maybe overkill but better safe than sorry.
Car has a few nitpicks like a rattling exhaust and minor pan leak (I need to get rid of the crappy NAPA gasket and get the real Mopar one) and I have to tweak the valve body as it likes to shift a touch later than I'd like at light throttle...
There is utterly NO harshness or vibration caused by the Chevy trans mount, it worked like a charm.
All in all I'm very pleased with the upgrade, I'll try and post a trans build up soon. Go for the upgrade! This is an awesome mod for our old Mopars!
Gary
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