I would to know why my 383 stroke wont pass 4500 rpm with 1.5 drive 23p 17ft ski boat I hope your guys help me again ,boat start run ,but I fell I did not get all power from that engine
engine set up 4 bolt block ,030 over,+13 dish piston,3.75 crank,lt4 hot cam ,1.5 roller rocker,64cc aluminum head with ss 2.02 intake valve, air gap intake,edelbrock 1409 650 , HEI Malloy distributor,33 degree total timing. Carter pump 6psi, running 91 fuel, by pass check valve .thanks please let me know

What speed you hitting at 4500? Do you have another prop to try? Doesn't sound over propped, but a ski boat has a hard time pulling skiers up with 23 or longer pitch. And a 17 foot boat has no business over 60 mph.

A 600cfm Eddy is tuned for a near stock 350. I do know that Edelbrock recommends a 800AVS on 400 or so hp383's.

That said, I have only used Eddy 600's on stock 350's so I will be of no help helping you tune it.

BTW: what do you mean when you say "by pass check valve" ?

Also, the carb is correct for a pass car use. Would run that 383 just fine in a camaro. Take just about any v8 automobile and put it at full throttle. Somewhere between 5 and 15 seconds later you hafta pull up on the gas pedal just about anywhere but a NASCAR track. In a boat, you are just coming up to speed...

i remove check valve in tank but it don't make any different ,and install new back in

[QUOTE=dereknkathy;4552312]What speed you hitting at 4500? Do you have another prop to try? Doesn't sound over propped, but a ski boat has a hard time pulling skiers up with 23 or longer pitch. And a 17 foot boat has no business over 60 mph.[/QUO
48 to 52 mph i was try 25p laser but i get slower .

i like to take for tune but i can not fine any tune shop in Lincoln ne,the big thing i worry my valve spring i was used it with new ls6 spring,i am not try to get this boat hit 70 mph but i would to know what i did wrong with engine ,last year i check compression every cylinder it got 170 to 180 .

yes sir ,but it wont make different i install new one in

Try a 21" pitch prop. What exact hull are you dealing with here?

Let me get this straight... you have a 17' boat, spinning a 23p prop and at 4500 rpm you only see 52 mph?

1.5 ratio drive?

Speed GPS?

The tach right?

THe prop ugly?