Re: Auto engine same as 350 mag?
A truck cam is quite similar to a marine cam, so if you pull the engine from a truck, you shouldn't need to change anything internal. If you pull one from a car, you'll want to change out the cam, because it won't be set up for as much torque, and torque is important in a boat.
You MUST use the marine accessories (Flame arrestor, starter and alternator are a must). There are a few rare individuals who will argue otherwise, but they're the ones who, more often than not, prove that Darwin was onto something with his "natural selection" bit.
So grab a block out of a truck, and swap all the accessories over, and you should be good to go.
Since your block is a 1992, you'll need a post-86 block, so get one from a newer truck.
Also, you'll need to replace the casting plugs (freeze plugs) with brass ones. Raw water will corrode the original ones. You can get a set of brass plugs on Ebay for about $10.
If you want a little extra oomph for not much money, you might consider putting a pair of Vortec heads on it. You'll gain about 30HP, more toruque, AND better fuel economy. There's a little more to the Vortec upgrade than just bolting them on though. You'll need to check your valve clearance, and get a Vortec intake.
All told, you can do the upgrade for under $250 if you can find some Vortec heads in a salvage yard... If you can find the heads, at the same yard you pull the block from, you can just pull the heads off the block you want, and bolt the Vortec heads onto it, and you'll only be paying for one long block. If you go that route, you can probably do it for $150 all told.
