Re: 4.3 vortec head and 4 brrrel swap
It is the best bang for the buck upgrade you can do. I think it is good for around 40HP if you do both. I had a 1996 Wellcraft with the 4.3L Vortec motor with a Holley 4V and it was pretty quick. With a 21P prop it would do 48MPH with a light load, and my Wellcraft was a heavy boat, about the same size as yours though. I have heard that the plain cast iron intake works just fine, or if you are not in salt, you could get a nice aluminum intake. Have you checked compression in the motor lately. If it is low, now would be the time to swap it all out if the motor is tired.
