just another newbee

[cheech]

i am new to the water world, what would the diff. be between tuning a motor for a boat (bbc). do i run the total timming the same as a car or will the motor take more (it is hard to here or feel the ping). do i build the motor for low end (3500 to 5500) power band or can i build motor power from 4500 to 7000 and then just use nitros to get me from 2500 7000. what does the pump like ( what will the pump do). if i use an impeller that lugs the motor at 4500 will i overspeed the impeller

[Jet City]

Since nobodies jumping on this I'll add what I know, as far as timing is concearned you would generally use a tad less than in a hot-rod since the engine is under constant load. I myself see no gain beyond 34 degrees full advance (in by 3000 rpm) on my jet-boat. As for the engine, build it for peek power output only, the engine will spin the pump very quickly to whatever it can achieve based on impellor cut and clearence, etc. vs. horsepower (much like a loose converter). For example if you had a Berkeley pump with an AA impellor, it would require 633 hp (@5500) to spin the pump to 5500 rpm, if that is where the engine peaked there would be no way to spin that loaded pump any faster.

[cheech]

thanx jet, i thought i was getting blacked flag for be a newbee. so do i just go for the horse power and skip the torque issue. i can make a huge gain in torque with the nitrous at a lower rpm (when i need it) and not have the motor built for full tilt. plus i do not have to spin the motor past 6500. i can keep the motor mild and low on maint. 468 with 4-bolt splayed caps(steel),i-beem rods with good bolts,10 to 1 flat tops and rec port heads.matched induction system (demon carb.)and msd controls for ign, and timing. i think i can get at least 500 hp on motor and add 300 from the bottle. should be able to push a boat at a pretty good clip. i don't know enough about jet pumps (yet) to determin speed or acceleration. a friend of mine said the people on this site are at the top of the food chain in the fast class.
is there a cyclop out there tod said that you are the man on pumps. i work with him they call me jay.

[youngster]

cyclone jay,...cyclone!!!!! he seems to be the one to answer all of my ques. about pumps w/o all of the bullshitz!!

[Jet City]

I'd ask the question again on the "just jets" forum here... http://www.***boat.com/forums/forumd...?s=&forumid=14
You'll get alot of opinions, just like what you already know about cars, building a fast boat comes down to a well selected combination of parts. Cyclone is a good one to ask, he has one of the fastest lake jets around.