This is a discussion on 5 speed swap within the Classic Tech forums, part of the Classic Mustangs category; i want to convert my '70 mustang sportsroof with a 351W and 4speed top loader to a 5-speed. ive read ...
i want to convert my '70 mustang sportsroof with a 351W and 4speed top loader to a 5-speed. ive read the info on MODERN DRIVELINE and STANGNET. my question is does anyone know the weight differences of the toploader, T5, 3550,TKO. also what are the torque ratings of these transmissions. i have raced my mustang at the dragstrip ( best time is a 12.38@112.8mph) but have been inconsistent with the original toploader with the original Hurst shifter. the mph indicates (quartrjr) approx 425rwhp. what vehicles were availabe with the tremec 3550 and TKO? i have 4.11 gears in the 9 inch rear and would like to have an overdrive to better cruise on the highway.
Why not buy a gear vendor? There are some that are rated to ridiculous power levels that will allow you to have the overdrive that you need. It will cost about the same as a new transmission and misc parts but without the hassle of swapping.