After seeing the current engine, I take it keeping it below the hatch isn't a concern!:)

383 Stroker!!!! :D

better put some wings on that thing too :) thats really going to be something when its done.

Kent,
A 502 is tempting, but then you start talking a lot more $$ for things like exhaust, and all the other bits you'd have to get. Ive heard of some pretty nice 383s being built that can see 450+ reliable HP. Although the guys that brag about the reliability, never mention it a week later when they break. If i recall, that motor is pretty new, and you have a lot invested in it, so reusing a good amount of parts is nice, if you can do it. That 18 may sit a bit low with the BB in it. I have a 502 in my criterion, and THAT sits pretty low at the stern.

Any idea what went wrong with this motor?

Hey Kent,
Isn't that an AlphaSS drive in 1st pic? I thought those Donzis came with SS ... though maybe I've got the wrong year and I'm :confused: :confused: :)

Not an Alpha SS. Old stlye Bravo 1 with a Nose Cone.

McGary911 - The crack is from a helicoil in the deck to the water jacket. Minor, but enough to let water through. The block has a lot of hours on it even though it was freshed about a year ago.

22 votes for the 383
20 votes for the 502.

I'll split the difference and go with a 406.
6" 4340 rods, lightened forged crank, JE pistons, internally balanced 9.7:1 compression and using my Sportsman II heads and lopy cam. I should see a slight increase in HP and Torque.

I do like the idea of having the big cubes in the small boat, but then I'll have to put a bigger tank in.

I'll save the bigger motor for the next project. Also with the smallblock, I can put those 283 ci stickers on the flame arrester; and until I crank it up.... lol :)

A buddy of mine has a 383 with 475hp in a 21 minx. He loves it and it is very reliable. It runs 77 all day.

probably look pretty neat with a canopy too.....

A couple of you mentioned 406. I assume you're thinking of using the siemesed bore 400 SBC block. I don't recommend this with a salt water open cooling system. The steam holes are too small and would be easily clogged with corrosion. They can NOT be drilled oversize either because of their proximity to the head-bolt hole. Also using this block would require you to have your heads drilled with steam holes. Using the 400 small block IMHO would not gain you enough extra power over the 383 to justify the added cost, not to mention your reliability would be down the drain. If you want to stick with a small block I suggest the 383 with 5.7 rods. Go to the extra expense and opt for the steel crank I have built many of both motors and there is no discernable power difference when built right.

Roby