74 dodge dart tranny issues
The only 4-speed overdrive (non-electronic) automatics that bolt up to your engine are the A-500 (based on the small, 904 3-speed) and A-518 (based on the larger, 727 3-speed) series out of trucks. They are good transmissions, but the overdrive units are in the tailshaft and are HUGE.... so big, in fact, that while you CAN put one behind a 318 in an A Body, it requires cutting the floorpan extensively, and completely re-configuring the rear crossmember (tranny mount crossmember.)
It's not a job for the faint-of-heart.... and whether it's worth it, is up to the individual.
An alternative plan is to install an 8.75" rear end, which has a drop-out center section, with ratios available down to 2.73:1, I believe. Get a third member with those gears and some 29" tall tires on the back, and you won't miss an overdrive. That combination should yield 75 mph at about 2,500 rpm, including converter "slip."
Changing final drive ratios is a snap in a car with an 8.75" rear.
The only 4-speed overdrive (non-electronic) automatics that bolt up to your engine are the A-500 (based on the small, 904 3-speed) and A-518 (based on the larger, 727 3-speed) series out of trucks. They are good transmissions, but the overdrive units are in the tailshaft and are HUGE.... so big, in fact, that while you CAN put one behind a 318 in an A Body, it requires cutting the floorpan extensively, and completely re-configuring the rear crossmember (tranny mount crossmember.)
It's not a job for the faint-of-heart.... and whether it's worth it, is up to the individual.
An alternative plan is to install an 8.75" rear end, which has a drop-out center section, with ratios available down to 2.73:1, I believe. Get a third member with those gears and some 29" tall tires on the back, and you won't miss an overdrive. That combination should yield 75 mph at about 2,500 rpm, including converter "slip."
Changing final drive ratios is a snap in a car with an 8.75" rear.
