OK so first off i am new here and currently a new boat owner of a 1978 southwind jet. I just built a 460 and put it in the boat an it runs great except the fact that it wont run over 3,500 Rpms. Now im not expert but im sure a 460 big block in a boat should run higher than that right I have a 460 preformer manifold with a holly double pumper carb. mallory distributor with MSD coil. The guy that i bought the engine block from told me to run a tourqer manifiold and i didnt cause at the time i was just trying to save money. So if you guys could give me any hints to as what i am doing wrong or doing everything wrong just call me a dumb ass  i am fine with it i am new to this so work with me here either reply back on here or email or text me 805-453-4217 i would be verythank full for all the advice i could get

What GPS speeds are you running at 3500? What is the engine doing at 3500? Cutting out? Shutting off? Or is that all she's got?

Check pump for duct tape....

HDriderTH: The pump in the jet?

Nordie: i dont know what is in it. its a berkeley  jet  not sure what kind of impeller is that something i could find out if i called manufacture. If it is a aa impeller what new impeller would you recogmend.  An should i put the tourker manifold on?

i think im set at 10 ? i would have to ask my friend who timed the engine for me. um sadly no  i dont have a diff carb. You think its to big for that engine ?  i think im going to have to get a better manifold to work with the carb and the rest of the engine.  My engine builder told me to get the tourker to run on the boat but i didnt have the money at the time nowim starting to think i should just get it.

All the things you mention help the engine to run more effeciently, however you need parts to make more HP, such as heads,cam comp ratio etc. Again not being familuar with jet pumps and what HP they demand, I would say as you explain your motor I would say you are closer to 300-325 hp .

Thank you all for the advice. crewchief i will take a look in the pump  because i was just at lake san antonio and there was stuff floating everywhere. 

Should i be looking into bigger heads anyone?

Ford casting numbers are visible on the outside of the cylinder heads (will be something like D0VE-A...). 

Post the casting numbers and one of the Ford guys will give some opinions about what you have.

exactly were on the heads are they located

I'm no expert on here like the rest of these guys, but I had the exact same issue but mine wouldn't go over 3200. I was running a vacuum advance distributer and my secondaries were never opening due to not enough vacuum, basically it was starving for fuel and running like a 2barrel.

All good suggestions are waranteed, however you would be most benifited to be sure the engine you have is runing the best it can. That would be correct timing, all vacumn accesories are working properly, dist and carb. Correct jets in carb. I would run a single wire HEI dist simple, work well.
When all that is correct than you can advance to different heads, manifold,exhaust, bore size etc. All the accesories you mention don't amount to more hp only to help in obtaining the above. When the engine is runing the best then what it has to push,turn pull will come into play. EX. disconnect all compentents and turn the engine to any rpm you want, hook it up its a different story. Everything componet on or hooked to the engine is relevent to its performance.