I'm changing my "fixed" Turbo 400 into a variable pitch 400 with a new pump and a re-manned torque converter. I'm putting this behind a 1964 401 and I need to find the correct flex plate and ring gear. Does anyone know if the flex plate on an earlier 401 (say 1963) will fit this application or do I need to go with a 1965-67, that would have gone with a Buick Super Turbine 400 from the factory? Also, I haven't got my torque converter yet so I'm wondering if the ring gear will be on the it, like earlier 401's. If not, what are my options for ring gear? I didn't get a flex plate or anything behind that when I got my 401. I was given a 1965 crank shaft and the guy I got it from said that was the ticket because I could then use a 455 flex plate/ring gear for the Turbo 400. Does that sound correct? I sure hope someone can point me in the right direction...my head is starting to hurt from all the scratchin'.
I can't answer all of your questions, but I can help a little. The later switch pitch torque converter will NOT have a ring gear on it. It needs to be used with a flex plate that has a ring gear I think the change to the 65 crank is necessary to make this work. 67-76 400/430/455 flex plate will not bolt to ANY nailhead crank. You need a 65-66 flex plate
