233HP Mercruiser re-Power

[bonanzaman]

Greetings, oh great marine engine gurus! I am most likely faced with re-powering my 76 Century straight outboard due to some dumb stick forgetting to winterize his new toy, and most likely cracking the block! (Mercruiser 351/233HP). If it turns out the block is indeed cracked, (I'll know in the spring when we fire her up!) can I use anything from the existing accessories, manifolds, risers, ect, if I want to upgrade to a big-block engine? In my place, if you wanted about 300hp what engine would be easiest to replace the old 233hp with??

Thanks for any suggestions!

*Forgot to mention, I've a bit of experience building auto engines, but new to marine!

[stonebreaker]

Did you say 351? Is that a ford engine?

[bonanzaman]

Well, that is the displacement shown in the Ops manual that came with the boat. It is a Mercruiser "Model 233" . The 351 displacement tells me it is a Ford-Based engine. Still trying to figure out this marine nomenclature!

[stonebreaker]

Well, why not just replace it with a 351 crate motor? Shouldn't be too hard to find a 300 hp small block.

[bonanzaman]

Yes, that would be a "long block" w/heads right? Any ideas where to look?
Thanks!

[Jango]

Yes it is a 351 Ford. Go to any reputable engine rebuilder and get a late model, 93 - 96 truck short block (roller cam engine ) add ported and polished iron heads and a 4 b carb lfor an easy 350 HP and 400+ ft-lb torque. The stock truck roller cam will work great.
If you want more, add some good flowing Alum Hds for another 100 horses and 50 ft-lb torque. ALL your existing marine stuff will bolt right on. Just be sure to use marine type gaskets.

[bonanzaman]

Cool, that's what I was hoping, that makes it a do-able project for me!
Thanks for that good news!!

[gonzo]

We sell 351 base engines for about $3700.00. They are new. A 351 GT-40 MPI complete is $7,000.00.