[Mario64]

Originally Posted by nickdee62

Great info, thanks so much! How about some transmission suggestions. Going with the 389, would like a 4 speed automatic. Anything good bolt right up?

a 2004R should fit in there. you will need the bop version. it should be built with billet internals and it will take the torque. it wont be cheap. i put one behind my 500 ci caddy, replaced the t-400. just needed a different slip yoke for the drive shaft. also use a lockup convertor. i used a b&m auto lockup switch. it can be set for different speeds. my caddy runs at 1770 rpms and 77 mph. perfect for freeway. 2.73 to 1 rear.
mario64

[mgarblik]

If you are using the original 389 that came in the car, make sure the block is drilled and tapped for an engine mounted starter. That was a transition year and I do not think all 389's had engine mounted starters or even a starter pad on the block for that matter. That will make a transmission change much more complicated, not impossible.

[Mario64]

Originally Posted by mgarblik

If you are using the original 389 that came in the car, make sure the block is drilled and tapped for an engine mounted starter. That was a transition year and I do not think all 389's had engine mounted starters or even a starter pad on the block for that matter. That will make a transmission change much more complicated, not impossible.

that is a very good point. who knows what has been done to these cars by all the different owners.
i was lucky when i bought my 64 grand prix. one of the previous owners had installed a t-400 and he half assed the neutral safety switch on the shifter.
i replaced it with a shiftworks shifter in the correct shift pattern.
mario64