building a jet pump (boat) motor

[Anonymous]

I have boat #0099 that I'd like to keep the inline 6 (233) but I'd like to mod it a little to help it run smoothly, and for long life. The need in the jet will be consistant torque throughout the rpm range more than anything. I expect this boat will probably cruise in the 3-4k rpm range...thoughts: I was thinking.
port/polish head/intake/exhaust
bigger intake/exhaust?


I dont think I want to raise the compression in it since mondo-horsepower really isnt called for...I'd love your experts opinion on what to do to this block.

 

[addo]

Hmm... It's probably a 223, but someone like Fred will confirm that. Definitely, the motor "belongs" in the Vintage forum, so I'll move it there. Nice that you've done the archaeology and got some good details; so many people just dig in without looking thoroughly first.

Cheers, Adam.