Ok thank you will make note to check pick ups on tank I planed on removing all gas and filing with new anyways. And I just had carbs rebuilt.

Ok looks like I have Mercruiser TRS 330 drives.

None of the pictures will showed up

The only way to tell if they are steel cranks are to look at the parting line on the castings.
"The best and most sure method for recognizing a forged crank is to look for the parting lines on the counterweights. A forged piece will have a wide, irregular rough patch. A cast component (shown) will have a very sharp, well-defined line where the mold was separated" but ALL crankshafts are made from steel

The guy sounds like he probably thinks his quadrajet 350 with ram exhaust manifolds makes 600 hp with its 3/4 race cam. Anyways since you have one of the engines apart post pics and id numbers of the parts you have. You can make some good horsepower with a plain 350 but you have to tailor it to a boat and most car guys and engine builders have no idea on how to build a boat engine. Camshaft selection is crucial to avoid revision. Stick with the advice you get from people on here and youll be ok.

Ok I spent a little time wrote down all my casting numbers off the crankshaft, pistons, cam, heads, intake manifold, and block from my Starboard engine and Google the casting numbers and here's what I got:

Pistons: Keith Black Silv-O-Lite Hypeeeutectic 1479H .30

Crankshaft: GM 1182 Forged Medium Journal 3.48" stroke 350

Heads: GM 333882 1975-77 350,400

Intake Manifold: GM 346250

Camshaft: CMC 1539

Engine Block: 3970010 Trucks & High Performance Apps 4 Bolt Main.

Definitely doesn't seem like a 400hp engine to me.
So what's a good Build for both engines, to make at least 400hp per engine using the 4 bolt block, forged crank, and maybe even the Pistons that I have. The block is .30 over bore from standard bore witch I guess make these 355's. The boat is currently fresh water cooled at the moment, I bought 2 Identical heat exchangers from a 454 mercruiser and plan on installing on engines because I do want to be able to take her out in salt water. I will post some pics of my parts not sure why last pics not show they showed when I posted them.

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