1987 3.0 engine rebuild

[Xavierbest]

I have a 1987 3.0 omc I'm rebuilding. The head is cracked and it's none repairable. I was wondering if I could get a high output head from a 90s engine? I figured since I'm already rebuilding it might as well do some upgrades here and there to make a little more power.

 

[Bondo]

Ayuh,..... There were a few slightly different head castin's over the years, but the 3.0l has never put out more than 140 hp,....

 

[Scott06]

Best way to get more power out of a 3.0 is swap in a 4.3.
if you want to use the newer head i think this adapter will make your existing manifold fit the newer head. https://www.michiganmotorz.com/mercruiser-exhaust-manifold-adapter-plate-kit-high-output-3-0l-engine