120 inboard rebuild question

[third times the charm]

Okay I'm going to rebuild my engine in my Starcraft at some point this year and I have a question.
Now I will have the machine shop do my work as far as the head, and the block. I want to have it bored .30 over and maybe the valves sized up in the head if possible. Maybe a port and polish job too? Anyway just curious what that would to for my engine performance, hp, etc, etc. I will upgrade the ignition system as well to ensure good fire. Just curious boys, any comments welcomed. Opened to all ideas

 

[achris]

Re: 120 inboard rebuild question

You might get 5-7 hp more.... Maybe 0.5 knots increase in speed...

If you want really improvement, toss the 120 (2.5l) and find a 3.0l worth putting in...

 

[grzzzz]

Re: 120 inboard rebuild question

I did all that and more to my 120 and was disappointed. Find an "organ donor", move the front mount up about 4" and put a 6 cylinder in. It bolts right up.

Grzzzz

 

[Fishermark]

Re: 120 inboard rebuild question

I'm with Chris on this one. I have been in a boat that went from a 2.5 to a 3.0 and the difference was amazing. The plus side is the swap is very easy and straightforward.

 

[third times the charm]

Re: 120 inboard rebuild question

Well, that's not what I wanted to hear, but that's what the forms are for. Well I got nothing but time on my side, so I will just look around for a donor. Thks fellows, appreciate the info.

Well at least I can spend that rebuilt money for a compete setup plus the boot from when I sell my current setup, all good.

 

[thumpar]

Re: 120 inboard rebuild question

When I have to rebuild my 2.5 I just plan on going to a 3.0.

 

[old islander]

Re: 120 inboard rebuild question

Parts for that 2.5 are getting harder and harder to find. And Expensive. Swap in the 3.0. That motor is still being made today and parts are A'plenty.