4.3 vortec to mercruiser conversion

[jknowles123]

Hey all, I recently bought a boat with a 4.3 mercruiser and blew it up on my first trip on the water....

I have a good 4.3 vortec donor engine.

Looking for recomendations for a good marine cam to get some extra ponies without destroying reliability. Also, will I run into issues with stock rockers running a slightly more aggressive cam?

If I can get my hands on a 4 barrel intake I will go that route as well. I will definitely be doing flat top pistons.

 

[tpenfield]

Welcome to iBoats. . .

Comp Cams has some marine cams. Generally marine cams are going to be mild and have a decent amount of lobe separation and minimal valve overlap. So, it is a bit difficult to get many extra ponies with the cam.

@Scott Danforth and others should have more specific input on the donor engine. Ideally, you will want to use many of the fuel, exhaust, and electrical parts from the blown-up engine.

 

[Bondo]

Hey all, I recently bought a boat with a 4.3 mercruiser and blew it up on my first trip on the water....

I have a good 4.3 vortec donor engine.

Looking for recomendations for a good marine cam to get some extra ponies without destroying reliability. Also, will I run into issues with stock rockers running a slightly more aggressive cam?

If I can get my hands on a 4 barrel intake I will go that route as well. I will definitely be doing flat top pistons.

Ayuh,..... Welcome Aboard,..... What vintage is the original motor,.....

Fix the fuel delivery issue, as it looks like you detonated that one to death,....

 

[Scott Danforth]

Hey all, I recently bought a boat with a 4.3 mercruiser and blew it up on my first trip on the water....

I have a good 4.3 vortec donor engine.

Looking for recomendations for a good marine cam to get some extra ponies without destroying reliability. Also, will I run into issues with stock rockers running a slightly more aggressive cam?

If I can get my hands on a 4 barrel intake I will go that route as well. I will definitely be doing flat top pistons.

The 4.3 has always been on the raged edge of reversion and detonation with a stock can

If you want more power, go with vortec heads and a 4-barrel

What vintage is your current motor

What vintage is the vortec motor

Is the vortec motor a truck motor or a marine motor?

 

[Scott Danforth]

And most importantly what are your power goals?