427BB in a boat??
 

Lookng at a older boat that has 427's, aluminum heads, stellings headers, and dominator carbs.

First off, I would assume that dominators are way overkill on those motors, and are probably killing performance and more than likely washing down the cylinders.

my question is, were the 427's ideal to run in a marine app? If I remember right the 427's were internally balanced, and good engines.

Would I be better off running them or just yankin them and selling them to some older corvette guys?

mt,

427's are no different than any other Big Block Chevy. They are a little smaller, but like to turn higher rpms. Properly setup I dont see any problem with them in a marine application.

There is nothing wrong with the dominators if they are set up properly and are the correct size for the hp the engines are making. They will only "wash down" the cylinders if they are improperly jetted or have another internal problem. That can happen with any carburetor.

I doubt you will get much for the engines in the automotive market unless they are fresh water cooled and have a Corvette or other HP engine code on them. I tell my customers to stay away from used marine engines like the plague. Only exception is fresh water cooled ones and even then I tell them not to pay too much.

If they run good, I would leave them alone. Why mess with them ?????????

Just my opinion,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

Good info, thanks Bill. What kind of rpm would be a safe range on a 427? I need to know what type of cam, lifters, and springs I guess.

i have 396 punched out to a 427, port and polished heads with a new marine cam,,, desk top dyno says 485 hp with about the same torge new pistons , i put a 502 in the boat , make an offer scott

mt,
First thing I would do if you buy the boat is to run it some and see what it does now. You need to find out what the WOT rpm is, that combined with prop size, weight of boat, drive ratios etc will give you some idea as to the horsepower the engines are making now.

Without some information from the original engine builder, its going to be hard to pick a camshaft. You really need to know the compression ratio to make a good choice. The cams that are in the engines now might be the ideal ones for the combination.

Bill

Just like any build, it all comes down to the parts used. If it were an all fordged assembly, with ARP fasteners and good heads, 6000RPM should be no problem at all. Remember they have a shorter stroke than a 454 and rev easier.



Darrell.

I have to find out more info on the builds. Ok, another question, compared to a 454, which makes better power for a boat, a 427 and 454?

Well, if everything being equal the 454 is the better motor. Remember the saying, " there's no substitute for cubic inches". It's true. Bigger motors make more torque and hp easier. Still, if the deal is right, and the motors are built correctly, it may be worth it. BTW, what type of boat are the motors in. Personally, the 427's would be better in a smaller lighter boat, rather than a heavy rig, where you would want more torque.


Darrell.