[taylorsgump]

I have a 1963 Pontiac Grand Prix with a 1964 389 2bbl engine with the Slim Jim trans neither are operating. Any suggestions on a new engine and trans. I tried finding a 389 in the Greenville SC area but not having any luck.

[tom s]

With a 64 engine you could use a turbo 400.Look into rebuilding and up grading you 389.Tom

[steve25]

There were 4 different 389 2BBl auto trans models available in 63 with the base line engine being only 215 hp.
Even if you had luck finding a newer 1966 389 motor that’s 60 years old now would you just drop it in if it ran, but was not rebuilt?

Why is your what I guess is original 389 not running?

[sdbob]

I put a 65 421 in my 63 in 70. Broke the borg warner 4spd trans twice. Put a turbo 400 long tail shaft in it. I think I used stock motor mounts. I used a turnbuckle to help with engine torquing Turned cross member around and used a steel plate to mount to crossmember to trans mount. I had stk manifolds on for a while then put 62 SD
complete exhaust on. Carb linkages worked. I used 65 2+2 console and shifter. Still have trans has a TransGo shift kit in it. Good luck.

[tom s]

Steve,he said it is a 1964 engine in his car!Tom

[steve25]

There really was not any change in the 63 and 64 motors other then the casting date codes.

[Goatracer1]

1 Big change in 1964 was the ability to bolt the starter to the ENGINE. This makes installing a later transmission much easier. If you have to rebuild an engine consider rebuilding your 389. Bore it out to 400 and use later heads and valve train. You already have all the pullies and correct brackets (I hope), plus timing cover and oil pan. You then can decide what you want for a transmission. You will probably also have to rebuild a transmission so you can use a T350 which fits the easiest and rebuilt correctly is plenty strong enough. A T400 will work with a little tunnel clearancing or you could install an overdrive trans. Do NOT rebuild the ROTO. Don't forget if you change the transmission you will have to modify the shift linkage and change the neutral safety switch. One for a street rod that attaches to the trans instead of the shifter works well. Good luck.

[taylorsgump]

Yes, the Pontiac was built in March of 63 and the Engine is coded 64. I took the engine a part and the piston are toast the cylinder walls are not bad. It sat for a long time. Don't know about the original engine. Going through a rebuild would be costly I would think

The story on the GP is some guy from the Boston area bought the GP and then went to Vietnam probably in 68 or so, I believe he was an officer because there are stickers for an officer in the Airforce on the front bumper. He did not make it out and His brother took over the car and beat it up. I tried to find more out. Looked up every Name in the Airforce from Mass. and tried to corollate them with the car but no luck.

I would like to put it together stock 389 2bbl but I think that is wishful thinking.

Thanks to all for your input.

[sdbob]

When I did mine I dont remember hammering the tunnel.400 trans may have been close. I may have 'adjusted' the angle I dont remember. I think I used the the stock crossmember mounting holes just turned around.

[J.C.you]

I have a 52k mile 63 cat 389 and slim Jim. Ran good when pulled