big questions

[1979tarva]

hey i have a 79 tarva jet boat with a 460 and comp cams jet boat cam holley 650 carb
1 im only getting 3000 rpm out of the motor in the water its pretty fast is this normal??
2 what setup do oyu use on your carbs mine came off a truck so im guesing that it needs a diff power valve it seems like the secondries arent opening what do you think?
3 what are the best baffels to get i went out today and got stopped by the lake cops they said it was a little to loud but only 91 db at 4 feet and i needed baffels he didnt site me and let me go out for the day which is nice and its the first time ive been out since 2003
thanks for helping me

[Cheap Thrills]

just a couple of questions to help clarify your questions....
1 ~ 3,000rpm on what impeller ?
2 ~ What carb ? the power valve isn't going to do anything as far as the secondaries opening is concerned. There's several here than run vacume secondary carbs that can help you better than I could. I hate the damn things. so I run a DP so I know the fookers open up when I mash the go fast pedal. :D
3 ~ Don't know about the baffles we don't have that problem where I am yet, but I'm sure it's comming. :rolleyes: OTs or Thru Hull ?
C.T. :wink:

[1979tarva]

its a vac secondary carb i think its an a impeller but im not sure it says ab on the plate on the pump the baffels are part of nps regulations which seem to suck lol i have through transom exhaust

[Devilman]

its a vac secondary carb i think its an a impeller but im not sure it says ab on the plate on the pump the baffels are part of nps regulations which seem to suck lol i have through transom exhaust
You have thru-transom exhaust, but they are still givin you a hard time about noise? Damn, seems pretty strict. I bought a set of Bassett baffles for insurance, but have yet to run anywhere that required them. Long live the open header. :crossx: Last boat I heard run with transom exhaust sounded like a Toyota...

[1979tarva]

the cop said im basiclly not allowed back to the lake till i fix it so i guess ill fix it it was only 91.5 db and the limit is 90

[SmokinLowriderSS]

You have thru-transom exhaust, but they are still givin you a hard time about noise? Damn, seems pretty strict. I bought a set of Bassett baffles for insurance, but have yet to run anywhere that required them. Long live the open header. :crossx: Last boat I heard run with transom exhaust sounded like a Toyota...
MY boat doesn't sound like a Toyota!!!!!!!! :argue:
'Course, I do have TT Lightning headers and 4" outlets, yep, long live the thunder of an open header, I don't mind it. :D
I'm surprised he's making that much noise TT, I cannot measure mine but as my exits are right at/under the water line at idle, Lowrider is a quiet idle. There is a reason it is called the loud pedal tho.LOL :crossx:

[SmokinLowriderSS]

Well, a jet will only let your motor spin as fast as you have HP to force it, it's like a dyno effect. First, check your tach, I'd BET it's wrong. 3,000rpm on a berk A takes 85HP on a tight pump. Even a Berk AA only needs 99HP for 3,000. Once you get that fixed, then we can look at other stuff.

[Devilman]

MY boat doesn't sound like a Toyota!!!!!!!! :argue:
'Course, I do have TT Lightning headers and 4" outlets, yep, long live the thunder of an open header, I don't mind it. :D
I'm surprised he's making that much noise TT, I cannot measure mine but as my exits are right at/under the water line at idle, Lowrider is a quiet idle. There is a reason it is called the loud pedal tho.LOL :crossx:
Well, not a real Toyota.:D It was factory logs & stuff on a stock Olds. Just about everybody I know is running OT or TT headers, so hearing that boat run was waaaayyy different than what I'm used to. I looked into TT headers awhile back, just a lot of coin. I still ain't ruling them out if I ever decide to buy a new set. :rollside:

[1979tarva]

the boat goes 40mph on gps at 3000 rpm is that pretty good for a 21 foot boat or should i try for faster

[SmokinLowriderSS]

Yea Devilman, they are spendy. As much as I would have liked to have the Bassett tri-Y's, I could afford a set of Lightnings (and then found those used. LOL). I am liking them tho, and it looks like OT's are getting so much trouble these days from regulators/LE that I am glad I have mine TT.
40 at 3,000 (if that tach is right, which I doubt) is really super. 40 @ 4200 with a "AA impeller is more likely I suspect. Want to go faster, it only takes HP, and that only takes $$$$$$$. Also setup on the drive helps too, and that only takes $$$.

[GunninGopher]

the boat goes 40mph on gps at 3000 rpm is that pretty good for a 21 foot boat or should i try for faster
That is really great, assuming that your data is correct. If it is, what is you peak RPM/Speed?

[BrendellaJet]

You should be getting way more rpm. That motor is probably capable of 5000 rpm minimum. Id bet you could use a little more carb. You can replace it(750 maybe) or rebuild since it sounds like it hasn't been used in a while. Id be looking for high 50's maybe even low 60's unless that hull is a real brick.

[1979tarva]

in the water the boat maxes out at 3000 rpm and 40 mph im thinking the secondaries arent opening and leting me go faster but im not sure the boat is kinda heavy its 21 feet nd i can really feel it behind the truck.
i need to get the exhaust done first to go to the lake and see whats up my prob is that i have 3 in. exhaust and all the slip in mufflers are 4 in. any ideas?