Bathtub Piston question

[rho]

Are there any bathtub pistons that would NOT work with a 121 head?

Reason for the question is that my bottom end currently has bathtub pistons and I was going to install a 121 head on it, soon.

Thanks

[jpcapoc]

According to Mike McCartney's restoration manual, the raised bathtub is compatible with the 121 type cylinder heads. According to him, these were the pistons used in the early tii. Apparently there are several versions, which give compression ratios between 9:1 and 10:1.

[Harv]

I had them in my last motor with a 121ti head. I put in 46mm intake valves and didn't have any problems and had a 9.7:1 comp ratio after shaving the head and milling the block.

John

[jpcapoc]

I had them in my last motor with a 121ti head. I put in 46mm intake valves and didn't have any problems and had a 9.7:1 comp ratio after shaving the head and milling the block.

John

Did you modify the timing gear to advance the cam timing to compensate for the milling of block and head?

[Harv]

No. With the aftermarket regrind 300 cam that I had it was very close to spot on.

John