Picked up a completely rebuilt 4 speed Saginaw from "Old School 4 Speeds" in Vermont. Dave is a great guy who has his own shop (I visited it and he had probably 12 newly rebuilt Muncies, T-10s, and Saginaws) at his home. He worked at dealership in Springfield rebuilding these same transmissions back '60s through 80s when they were covered under warranty, no questions asked ! A wealth of drivetrain knowledge. Also picked up correct original Saginaw linkage and competition shifter for Firebird from him, all adjusted ahead of time and assembled. Also got original refurbished bell housing from him with clutch fork assembled, new factory paint. His stock on hand is amazing. Shifter assemblies for most everything with linkages.
Followed Oldslow's advice and picked up a forged steel flywheel and upgraded Ram clutch from Summit. Went with his recommendation for 3.11 first gear ratio with my 3.08 rear. Also put in a new Yukon LSD with new Summit axles - old axles were shot with wear. (My rear end is GM, not BOP, so Yukon posi fit - easy install, backlash, shimming, etc)
Some issues with new z-bar linkage kit covered in separate thread that Big Chief and Oldslow helped me with. Arm needed to be cut, shortened, re-welded to clear master cylinder. I think this was due (?) to past frame rebuild (rust) and new motor mounts ... needed 1/8" less for clearance. Not sure ... but it worked !
Car gearing is beyond awesome. Oldslow was dead on. 4 speed is smooth, takes off like it has 4.11 rear, and cruises at 70 mph @ 2400rpm. I thought second gear would come on too fast with the 3.11 first, but it is perfect. I baby her, so am hoping the Saginaw holds up behind the 400's torque. Dave at "Old School 4 Speeds" said he put many Saginaws behind 400s back in the day with highway gears. He said "Don't beat it and she will last for decades" ..... we will see !
Thank you all for great advice and walking me through the manual conversion. Could not have done it without this forum.
