Thread:

how much h.p. to go 100mph

greg, how much h.p. does a v bottom 19' jet usually need to go 100 mph ? i have a 78 gt twin turbo. i finally hit 94mph but still working on it . wondering if i have the ponies. i have heard 850 hp should do it , i am pretty sure i have that .maybe more? i dropped the shoe 1/8,now it is still @ 1/8 inch above keel and i slowed down 2mph,the loader is now farther from the water? , legend ho-hum loader,not race. i am cavitating @ high eighties on up. unless i jet-o-vate it & ride the nose up. my pressure is only @ 15 psi at the intake . it goes up to @ 20psi when i ride the nose up. the shoe is not back cut ,the pump is berkley jg, impeller is legend AA1/2 with a preloader/inducer, GTH bowl & intake .i was told it rides real dry . i also had a place diverer,actualy a copy cat one on the boat,(blue max by jdh performance/precision? ,something like that) so i bought a new place diverter FTN & slowed down another 2mph with the red one , the common size they send with the new nozzle . i also am having a loader made. haven't got it yet , but do you have any recomendations, or for sure fire ways to get to 100mph? ( without nitrous) thanks, turbo wog

850 is enough for most v bottoms from what I have seen...Greg may know the boat and should be able to help. How many rpms?

Originally Posted by Sleeper CP

Observed on a 105* day ? Or corrected HP #'s ?

Sleeper CP

For me, not on a 105* day. Corrected #'s worked for my application.

thanks guys, i'm so close...98.9mph ahhhh .working with the loader right now

Originally Posted by turbo wog

thanks guys, i'm so close...98.9mph ahhhh .working with the loader right now

have you tried a smaller id ftn yet? i'd go there next, your intake pressure will go up some been playin with nozzle id alot here latel myself and never realized how much it affects the boat and mph.

Originally Posted by Sleeper CP

Year's ago our boat ran 99.8 mph for two season's couldn't get it to break 100 mph. Dumped more nitrous to it, blew a couple of holes in pistons and the damn thing wouldn't top 100.

Sitting on the sand bar one day scratching my head I pulled out the rev chip and it was a 6,800 rpm chip I replaced it with a 7,200 rpm chip and on the next pass it ran 102.

I was just a little pissed off

Sleeper CP

lol

Originally Posted by Sleeper CP

Year's ago our boat ran 99.8 mph for two season's couldn't get it to break 100 mph. Dumped more nitrous to it, blew a couple of holes in pistons and the damn thing wouldn't top 100.

Sitting on the sand bar one day scratching my head I pulled out the rev chip and it was a 6,800 rpm chip I replaced it with a 7,200 rpm chip and on the next pass it ran 102.

I was just a little pissed off

Sleeper CP

sorry man but i had to laugh, that is probablly something i would do to

It's Always Funny How Simple Shit Is, But We Always Do The Hard Stuff First Just Our Stuburn Human Race I Guess.

Originally Posted by IMPATIENT 1

have you tried a smaller id ftn yet? i'd go there next, your intake pressure will go up some been playin with nozzle id alot here latel myself and never realized how much it affects the boat and mph.

not yet, i need to get some smaller ones , i have the red .. i tried taking it out but i didnt' get to test good enough then put it back in i have good test data now so i will try it out for. so next i will take it out first , while i'm trying to get some more ftn reducers. it did seem that when there was glass out it loaked the pump & the rpm dropped & went slower.it did loose 2mph when i put the ftn on instead of the old diverter i think the old one was bigger diamiter but had straightning veins in it.

Originally Posted by Sleeper CP

Year's ago our boat ran 99.8 mph for two season's couldn't get it to break 100 mph. Dumped more nitrous to it, blew a couple of holes in pistons and the damn thing wouldn't top 100.

Sitting on the sand bar one day scratching my head I pulled out the rev chip and it was a 6,800 rpm chip I replaced it with a 7,200 rpm chip and on the next pass it ran 102.

I was just a little pissed off

Sleeper CP

i think i have mine set at 7200. maybey i should bump mine up just to check. for all i know the gauge is off like all the others. half the time they jump around or don't work. how fast does yours go on only motor, if ya don't mind me asking?pretty nice comprimise for a family boat