I am the proud new owner of a 68 with a four speed. Since the car isn't original, I was thinking about swapping in a 5 speed, for the short term, to help with my gas mileage until I finish my LS/M6 swap later next year. It just needs to be cheap enough to not inhibit saving for my LS swap.

Is there a factory 5 speed from maybe a mid 80's or early 90's F body or Vette that can be sourced cheaply, with a minimum of fabrication? I was thinking there must be a 5 speed that came in a Formula or Z28 that would be cost effective to drop behind my mild 350.

Thanks in advance for the help. I look forward to being a part of this community.

Scatter'd

 

The T5 trans put in the mid 80's will not hold up to the torgue of a decent 350. GM did put the T5 in with the 305 but did not offer it with the 350 for this reason. I know the Mid 80's Vets have a 4 speed with OD added on the end. It was a hi-lo thing. If you find one I would imagine it is pricey and not much better then the T5.

I seem to remember there is one 5 speed that was tuff but I can not think of the application of it. Maybe someone else will remember.

 

You're looking for the Tremec TKO (not to be confused with the weak T5 version): Tremec 5 Speed Conversion

 

Ditto on the T5, it won't hold up if you drive it hard. The Vette had a 4+3 that most Vette owners hated. The aftermarket-only TKO fits great in the tunnel, but you have to alter the crossmember, shorten the driveshaft, use a different slip yoke, and it requires a 26-spline clutch disc and a Ford speedo cable. With an unmodified TKO, you have to trim the shifter hole a little bit on the passenger's side. Keisler Engineering offers a kit with a modified shifter, crossmember, driveshaft, and speedo cable that is a bolt in for your car, no mods necessary. They also have a T45RS kit that is less expensive than the TKO and would hold up to just about any small block.