Big block torque converter pilot sizes

• May 9, 2019

• #1

KENTON

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can anyone tell me if the pilot hole in the back of a big block crank varies from one year to another? I’m taking automatic only. I know the torque converters change spline count between 65 and 66 but don’t know about the other side of the torque converter, (the pilot side) Thanks for your replies.

 

• May 9, 2019

• #2

R

R413

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BB is the same size pilot 1962 and newer.
Converter splines and input shaft diameter changed in 1967.
So it is 1962-1966 for the oddball converter input.

273 and 904 had some oddball pilot sizes in 1967. When compared to 318 and 727. Keep that in mind when swapping parts around.

 

• May 10, 2019

• #3

KENTON

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R413 said:

BB is the same size pilot 1962 and newer.
Converter splines and input shaft diameter changed in 1967.
So it is 1962-1966 for the oddball converter input.

273 and 904 had some oddball pilot sizes in 1967. When compared to 318 and 727. Keep that in mind when swapping parts around.

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Thanks, that answered my question.