bsranch

I have a 305 Vortec roller cam marine engine with a cracked block. #10243878. What year blocks can I purchase to put these parts in? The marine engine I have has less than 50 hours, everything looks new. Thanks for your help.

mjgord51

Now's the time to invest in a real motor and that would be a 350 my friend. I know some friends that have 1,000's of hours on there 350's.

Rednucleus

I'm a water skier - what kind of boat, yr etc. I assume freeze damage?

racer5039

I would get a short block 350, use all your parts on that short block, cam heads, intake and the like. Much better and head will flow just fine for a 350.

mjgord51

First of all the 305's crank will not work in the 350, it will need to have more weight added to the counter weights (dumb idea)... Second of all the heads are too small (actually the valves are to small) again dumb idea...Third of all the cam is a package deal for whats in the 305 (heads, intake, carb/FI, piston compression and the like's.... Why would you use a 350 block and put "down sized " parts in it even if you could which the crank doesn't allow you to in the first place, again dumb idea...

The only thing parts wise the 305 has in common with a 350 block is the stroke or rod length of 3.48 and the crank (305) has
"Down sized" counter weights.
Yes the heads will fit,but why would you (too small) there sized for smaller bores like the 283 (3.875) the 305 (3.736) 265 (3.75) and the 307 (3.875), 350 is (4.00) again why would you put puny small size valves on a 350 that would be "De tuning" or down sizing things, dumb idea. The intake will work but that also depends which intake is it or what you want to get out of it.

But hay Mr. racer5039 man you do what you want it would be your wasted money if you did that.