Engine replace from chevy 305 to 350

[Buck Horn Deer Farm]

I have a 1977 24' searay weekender with a chevy 305 (mercruiser 228 hp) That took a dump. The cam lost a few lobes and soft metal went through the bearings and all. This motor struggled a bit to get on plane. Should i rebuild this one? Should it have enough power for that boat? Or, Is this the time to replace it with a chevy 350 for more hp? and most important, can I use a motor that is from the mid 90's? (found one on line). What year engine should I be looking for?
I have a friend that has two chevy 350 marine motors that came out of a larger boat from the mid 70's. They are a pair of inboard motors one is right hand the other is left hand but will need rebuilding. Not sure I want to use the proper one.
Have you all got any info you can help me with?

 

[Doernuth]

Re: [B]Engine replace from chevy 305 to 350[/B]

Re: Engine replace from chevy 305 to 350

Don't exceed the horsepower limit of the hull. Also make sure that the gear ratio's of the outdrives match up unless you are replacing them also.

 

[Fordiesel69]

Re: Engine replace from chevy 305 to 350

Going to a 350 just makes more sense. Do not waste the time rebuilding yours as machining labor costs are thru the roof.

 

[thedillybar]

Re: Engine replace from chevy 305 to 350

Don't know anything about doing a swap...

Not sure what the boat weighs, but I think a 305 would have no problem getting it on plane and doing 30-35mph. A rebuilt motor w/ good cam might run a lot better.

 

[Fordiesel69]

Re: Engine replace from chevy 305 to 350

Ideally if you can afford it, go with a GM 350 vortec swap. There are some mods that need done but with research can be a very worthwile effort.

 

[sarantis]

Re: Engine replace from chevy 305 to 350

Tiring and expensive modifications.Better buy a complete 350 with A1 outdrive and check it good with a mechanic before you go. Your outdrive is pre-alpha,very old.But with a 350 will see a significant diference.

 

[Bondo]

Re: Engine replace from chevy 305 to 350

Is this the time to replace it with a chevy 350 for more hp? and most important, can I use a motor that is from the mid 90's? (found one on line). What year engine should I be looking for?

Ayuh,.... In 1979, the Dipstick swapped sides,...
About 86, the crankshaft bolt pattern changed,...( they make/ sell couplers for your drive in that pattern)
Around then the intake manifold bolt pattern changed also...
In 96, the Vortec heads came out, 'n the intake manifold pattern changed again...

You've be Nuts to buy a 305, when a 350 is the Same money....
I'd drop in a GM Goodwrench 350 Vortec, 96, 'n later, then adapt what needs adaptin'....