[Gaz64]

Agree with all comments from the lads above.

Idle speed (engine torque) versus torque converter stall (low or stock stall), is why it "drives forward".

You would find it will hold on certain hills, and then when they don't, which is complaint I get a lot of with Autos.

Loosen the torque convertor to 2500 stall rpm or so, and stay with EFI if funds allow. You will achieve a much better package.