i went from some 625hp 509s, to some blown 557s, it ran 106 on gps before, now with dynoed 850hp 557s it still only will run 106 it gets there alot faster but it seems to just stay there wont build no power at 5100 rpm, last year the transom was blackend by fuel,now theres no sign of fuel even my tailpipes look clean on the inside seems lean ,do you think riching it up will make it pull harder on the big end.

the answer is re prop it go with taller props will get more speed a little longer off the line

yes , but i spun32 bravos with 136 gears before to 5100rpm i still canonly turn them 5100 if i spin trim it higher it willgo to 5500 rpm but not gain any speed. should be able to turn those same props to 5800 with this set up. looks as if its lean on the big end.

Where was your hp and tq peak on the dyno? Smitty

going to look at the dyno reports tomorrow

Do a spark plug check after a wot run. Then you will know if it is lean or not. I think I read somewhere on OSO that someone ran their motor on the richer side and it ran faster. Do you have a fuel system in the boat for the higher HP motors ?

yes fuel system is fine,

long and short before this turns into another throw enough s*it angainst the wall threads borrow some taller props and see what she does

[QUOTE=johnnyboatman]i went from some 625hp 509s it ran 106 on gps beforeQUOTE]

Am i reading/quoting this correctly ?

What kind of boat ?

the deal is we added 400plus more hp it should spin the same props higher in the rpm band, more speed.correct