Man!!! 425HP in that little 19 footer?? I not sure if the block got cracked in the last freeze so I would hate to tear it down and waste time on it. I started to read on the difference between the boat and car engines and most say that the SS gaskets and cam change is it. How much HP would be safe on this boat?

Here is a link to the boat


http://beta.communities.msn.com.mx/G...to&PhotoID=658

That's a good looking boat and would be pretty quick with a worked over small block. You can easily gain 100hp over stock with the right parts. As to being safe, there are plenty of 19' boats running 400hp. PlumCrazy on this board has a 19'
Baja with a potent 383.

Marine motor differences are mainly the headgaskets, brass core plugs, cam etc... I've often heard marine engines should be set up a tad looser than spec but i've always built mine around standard spec with no problems.

If you have any reservations on a cracked block either replace it or have it tested before using it for a new build. If you want to go this route let us know as we can spec all the go fast HP parts you'll need.

As to the Alpha drive. They are rated at 300hp but many including myself have made them live long lives with much more. My 1992 Alpha has outlived 3 350-400hp small blocks in my 22' Challenger. Having a light boat always helps.

To keep the Alpha alive ......

Add a drive shower and synthetic oil
NO stiff arm hole shots. These are not jet boats
Wait until you get moving to go WOT
If you get the prop out of the water get off the throttle under reentry, coming back in WOT will either strip the gear teeth or break the driveshaft.

There is a reason Merc engines cost more...........they are worth it.

I'm sure Merc are good engines but I see a lot of boats that are a few years old that say they have new motors in them and they had Merc's to begin with.

I would like about 300hp and a bit more, but 300 would be fine. If I had one built I would use inconel valves, roller cam(marine grind) standard pistons. From what I hear, it is the valve train that takes the most punishment. Would a Vortex motor be a better start?

One other thing is that if you look at the link on that site and check out the rear of the boat i would like to run the exhaust straight out the rounded area at the bump rail with chrome tips. (I thing it would look great to see them there) The angle would be very slight and would a tip with the built in baffles keep the water out? Also, would the boat be to loud for normal use?

Merc's are the only way to go for a drop in, they are better.
If a newer boat has new engines, it was likely a power upgrade.

What is right for you, depends on your plans for using this boat.
Salt or fresh, lots of at idle cruising, skiing, long WOT runs, wave jumping, short blasts across the pond, or re-sale?

To build your own engine would not be all that difficult or expensive. If you are in fresh and don't use lots of gas in the season(or it's a non issue) , I would lean towards building a stout aluminum headed 350 or 377/383.

If you do more no wake zone cruising and some water sports and are more concerned about fuel consumption, I would look for a drop in MPI.

My own boat is getting a pair of re-man 383 MPI's with Bravo 1 Drives which I bought prom Pro-Tec Marine. My firsts plan was to build a pair of killer 383 carbed engines, but by the time I priced it all out, the new re-man engines and drive combo's were just a couple grand more.

I can understand why you think the Merc "BLUE" motors are better because they are hand built, but why are the black motors better?

Dave

I mean better than a GM Motorsport crate engine for marine use

try
http://www.dereberyperformancemarine...k_Engines.html

reasonable prices and I have not heard of any complaints.

merc reman has a 383 that makes some good power

I'm just wondering about all the cam and engine size thoughts...

If a boat engine is under heavy load from an idle up to 5,000rpm and the cam is ground for the best torque down low, then a larger engine should work less then a smaller one as far as the load?( lets say a 400 SBC ver 350) More torque, right? So if you get a zz4 motor that makes torque higher and has more HP but at a higher rpm, would and engine like that run good if you changed the gears in the drive? What kind of problems would happen?