What is the difference between a marine 440 and a car 440, also the diff between a 440 hi po and a stock chysler 440.
Thanks for the help.

Marine 440 could be reverse rotaion , cam should be different , possibly valve springs , boats don't get driven like passenger cars. Big thing to look out for is the cooling system type , you don't want one that was raw water cooled , meaning the water the boat is in goes thru the engine , especially if it was used in SALT WATER .

Difference between HP and non HP in a car , the 2 letters stamped H and P and depends on the year but mainly it's , the cam , carb tuning , valve springs , curve of the distributor , oil pan capacity , windage tray or not , exhaust manifolds , 67 - 71 the difference was roughly 25HP ....

Most 440 Marine motors weren't Hi-Po. Only the 440-6 Marine was.

Different parts on LH rotation;
oil pan
oil pump
intake manifold
carb
dist
alternator
water pump housing
water pump (raw water used Sherwood pumps)
exhaust manifolds

Different parts on RH (reverse) rotation;
all above plus
crankshaft
camshaft
dist drive gear
dist thrust block

Most were raw water cooled, and yes, stay away from one that was in salt.

Chrysler supplied and sponsored some pretty cool boat motors

Some NOS decals I have

You basically have no reason to want a marine block. Period. Especially ones run in salt water.

Well, I guess all this tells me to stay away from the 440 marine, the rotation, is that by the distributor.
Thanks

Actually the crankshaft and everything attached rotates the reverse of a car motor.

I don't think they are something to be scared of,the reverse engines were usually ran with a normal rotation engine and if it was a single engine they were normal rotation from what I've seen in the few boats that I've worked on.

Not all 440's are reverse rotation, only some that were used in dual engine boats. The reverse rotation bits can be changed out, that's not the problem. The real issue is do you want to build an engine that has had sea water run through its veins its whole life? Salt water rusts the hell out of a cast iron block and running freshwater through it isn't great either. Seeing as 440's are not that rare, I see no real reason to take a chance on a marine block.

Now if someone offered me a great deal on an old marine 426 hemi, I would be all over that. Well it would at least be worth checking out.

I always thought that marine mtors were balanced & blueprinted so they would hold together at 6K rpm,for hours on end,like going across lake mich.

While most marine v8's are setup to run at a steady higher rpm for hours on end, not 6000rpm. I would suspect a normal "high" rpm for one would be no more than 4500ish. They were cammed and propped for torq, not to scream. Unless we're talking about a race/jet boat kind of deal.

Not all reverse rotation marine motors were used in twin engine boats, many single engine boats use them.
95%+ of all Correct Craft, Moomba, Master Craft, etc ski boats use reverse motors. The idea is to help keep the boat level under power by using the prop torque to counteract the weight of the driver.
I wouldn't worry about a 440 used in fresh water. There are hundreds of Mopar race cars with nothing but water in the cooling system.

Daytona turbo,you're correct i was a little high on rpm but you get the just of it!

Interesting b5 bee, I've only seen one marine 440 that was taken apart and it was standard rotation. I assumed it was from a single engine boat, but perhaps that was one from a twin.

I've seen some fresh water lake boats with engines that were more crusted up on the outside than they probably were on the inside!

...and if the oil pump turned backwards, I don't think the motor would live too long.

If you do find a RH (reverse) Marine motor for cheap, buy it for parts. You'll get your money back from the cam and dist/oil pump drive gear as these parts aren't available new.