yorkman

Is a 1970 TH350 a direct swap for a ST300 in a 1968 Cutlass? Is the overall length the same? Will the ST300 driveshaft and yoke work? Will the converter work? I am aware there will be shifter and kickdown differences. Thanks, Bob

joe_padavano

This is as close to a bolt-in swap as you can find. I've actually done this exact swap. The TH350 is the same length, bolts right in, and uses the same driveshaft. Obviously the shift quadrant will only have PRNDL and not PRNDSL. If you have a factory floor shifter, you can get a conversion kit from Shiftworks to convert your 2spd shifter to a 3 spd. The only thing that requires a little fabrication is the TH350 kickdown cable. You'll need to cut a small square hole in the firewall just below the accelerator cable location. The stock kickdown cable snaps into this hole. You'll also need the TH350 accelerator pedal, which has the correct tab to connect to the kickdown cable.