SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: Brad @ SCJB on February 08, 2007, 06:55:16 PM

Title: Marine vs Street
Post by: Brad @ SCJB on February 08, 2007, 06:55:16 PM
I have someone who has offered me their Chevy 350 out of their Nova.....

Can I just drop it into a boat, or do I need to do major work to it for marine applications because of the constant WOT it will endure.

Title: Re: Marine vs Street
Post by: Ralph Brunt on February 08, 2007, 07:47:15 PM
well i dont know a lot but i will give this a shot. of course you can just drop it in a boat will it last at a sustained 5k probably not. bearing clearances are crucial (ask me how i know :( ) a small block will have to rev pretty high to make 500hp when a big block can do it at about 4500 rpm and lets not even get into the torque thing.  do you have a boat? if so what kind of hull?? how heavy? all these are things to consider. you can get the 350 sell it and get a big block and go from there, it's not hard to make a big block live at 5k.  just my .02 ralph
Title: Re: Marine vs Street
Post by: hotrod56cars on February 08, 2007, 10:09:10 PM
As with almost all of my jet boat knowledge, what I read was...

The cylinders on the marine engine need to be looser than a car engine, the cylinders get hotter in the marine ap. therefore expanding more requiring looser cylinder wall to piston clearences. So if that 350 is very well broken in you should get at least one full season out of it. If it's fresh, expect it to expire quickly. Hull design, hull weight, and driving practices will play a huge part.

I've got a friend that had the most reliable boat of all of my friends, a completely stock, broke in is a huge understatement, probably 100,000 mile 454 that lasted 3 seasons until he tried to show off on a sand bar pass throwing a engine rod.

I'm going with a car 454 I bought off of craigslist, easily a 60,000 mile engine, I just won't be showing off because my pocketbook won't allow it. I wish you luck, I know that's what I'll be counting on.  ::)