Swapping out a 305 for a 383.

[TilliamWe]

Re: Swapping out a 305 for a 383.

so i said 350 4inch .030 over with 400 crank is 383 um so are you,i said400 block 350 crank is 377,you say 372.oh i guess iam wrong i forgot to add .30 over.so a 350 is actually 360

Glenn, I was just pointing out that you were stating incorrect combinations. If you're gonna say something is a fact, say it correctly, that's all.

 

[GLENN M]

Re: Swapping out a 305 for a 383.

no problem my bad,377 and 383 are combos most advertised around here,myself i like short stroke motors with big bores.you state 4inch bore with 3.48 is 359.8cid,did you mean 349 cid.or am i reading it wrong.cheers

 

[DaNinja]

Re: Swapping out a 305 for a 383.

Fun times.
Thanks to all!

I think tomorrow I'll start ....

Smart tabs v. Hydrofoil
Ethanol in a boat
Alcohol in a boat
and maybe...

 

[proshadetree]

Re: Swapping out a 305 for a 383.

383 not a bad engine, 350 probably a cheaper swap, about the same on fuel dependent on fuel supply. As far as resale who cares if its a 383 or a 350 both have a good reputation of being fine power plants. No one said the 383 had to be a full race engine. They were originally built so you did not have to wind a small block up so tight. In a marine application you will barely exceed the 300 horse rating of your drive.

 

[TilliamWe]

Re: Swapping out a 305 for a 383.

I am sure if I typed 359.9, then it was my fat left index finger that hit the "5" instead of the "4". Indeed a 350 is actually just about 349.67 cid.

 

[GLENN M]

Re: Swapping out a 305 for a 383.

I am sure if I typed 359.9, then it was my fat left index finger that hit the "5" instead of the "4". Indeed a 350 is actually just about 349.67 cid.

yeah i knew that just thought it was funny corrected my mistake with a mistake.the two most common engine kits i hear about are 383 and the 377 which is based around the 4.125 block.you need the spacers to fit 3.48 [350]crank in block.i didn't know they were making a 377 with the 4.00 inch block,myself i like short stroke big bore engines,keeps piston speed down and kills some low end torque.cheers

 

[TilliamWe]

Re: Swapping out a 305 for a 383.

Yep, Mercruiser Remanufactured division sells both 377s and 383s. They claim that they are all 5.7s that they have taken in on sales of repowers. And of course they also sell brand new 6.2s, or now they are calling it a 377 also, which they get 350s from GM and add the 400s 3.75" crank. Short stroke motors are fine, if you have the components to spin them FAST. But Mercruiser outdrives are not meant to spin much over 5200 or 55oo rpms. With 5000 being the best top rev.
DaNinja, if a 377 reman from Merc could be had A LOT cheaper than a 383, that would be a good way to go as well.

 

[DaNinja]

Re: Swapping out a 305 for a 383.

Yep, Mercruiser Remanufactured division sells both 377s and 383s. They claim that they are all 5.7s that they have taken in on sales of repowers. And of course they also sell brand new 6.2s, or now they are calling it a 377 also, which they get 350s from GM and add the 400s 3.75" crank. Short stroke motors are fine, if you have the components to spin them FAST. But Mercruiser outdrives are not meant to spin much over 5200 or 55oo rpms. With 5000 being the best top rev.
DaNinja, if a 377 reman from Merc could be had A LOT cheaper than a 383, that would be a good way to go as well.

Thanks for the advise!
I'm going with a 5.7 Merc.
Part of that is imagining the wife bringing "her" boat to a shop and having to explain what they were working on.
I'd love some bigger power, but I'm sticking with Mercruiser (well Jasper) 5.7 in front of an Alpha I (Gen II).