I have a 1976 Corvette that I am going to install a 454 in place of the 350. My question is I found a 454 that was a marine motor at one time, it was rebuilt then installed in a an old 80's c10 pick-up.
Does anyone know if their are any advantages or dis advantages to a marine motor ?

 

you better start researching,
to drop in a BB in a Corvette you got to change a lot equipment !
all brackets, PS, Alt, A/C, must be BB corvette only !,
pulleys, water pump, maybe radiator, intake manifold, Breather, Hood.
possible front springs, this is not a pull out / drop in swap.

 

Yup..

 

I went to a 406 small block for the reasons already given. Also,..over the years I had accumulated quite a stockpile of smallblock parts. It just made too much sense to stay small. But make no mistake about it,...It may be small,...but it'll put a smile on anybody's face when you hear it idle and see the fenders shake.

 

I had herd at one time that the marine blocks had a higher nickle content for corrosion protection. Don't remember where I herd that at so not sure if its true or not.

Neal

 

I already know what I will need to do the swap, and the motor is complete from carb to oil pan including all assesories and brackets. I already know I will possiblely need a 4 core radiator. I have read up and searched for all the info needed, thanks. I am just curious about the motor itself being a boat ?

 

As soon as it got converted to passenger car use, any dissimilarities which would cause you trouble disappeared. From a practical standpoint right now it doesn't matter a whit.

 

Many different BBC engines went into boats, from base type engines to healthy crate motors. Post your casting numbers to see what you have. Typically only the accessories made them "marine" engines.


Rob

 

Having much more boating experience than Corvette experience (much more of a novice in the latter) ... I can tell you more here.

As mentioned it's accessories...yes.... but there might be other differences as well.

For example, the water pump is typically made to be using raw water (ie. ocean water being pulled in and dumped as you go). This means different internals to better handle corrosion. Seals and impellers are different. Impeller is typically bronze. It might also pump at a different rate than a typical closed system pump from a car.

Electrical systems in a marine engine are, typically, completely sealed. Two reasons, one is corrosion. Second fuel vapors. In a boat you don't have the luxury of much open air getting into the engine compartment. Thus fuel vaoprs accumalate. Many inboard setups have vapor alarms for this reason. Starter, alternator, distributor, etc.

Now your concern, or at least what I think it is, the engine internals. Yes they are different. The heads and cams are different because they are desinged for a different operation. Most boats have a single gear driveshaft operation. As a result, the boat engine is designed for low end torque (lots of it) and continued operation at medium to high RPMs. You have no gears in a boat to make the engine run at 2,000 RPM when you cruise. It's very different from a car. The carberator is also completely different. They use special carbs that can handle vibration and the beating a boat takes. A regular carb would just spill fuel out.

Other things are less important but you'll like want to change them. For example many parts are painted in anti corrosive paint. Very good and long lasting but not big on color.... LOL....

 

If the motor was used in a boat that operated in salt water, look closely at the water passages. Some marine engines use sealed fresh water systems, in that case you only need to check the exhaust ports, the only place that salt water would normally attack. If the motor had a raw water system, it would pump salt water through the block. Then you need to check the coolant passages and the block/head area carefully. Salt water and cast iron are not a great combination.

Usually the main difference is brass freeze plugs. Check them too for corrosion because galvanic corrosion can damage them in a salt water environment.

 

Not possibly need -- will definitely need.

Easy Route: purchase the 74 assembly instruction manual and use what you find for the factory big block installation. The AIM will show the parts and list original parts numbers for what you are going to need.

Good luck.