Need Jetting Help Dual 44 NOVI's ?Tricky?Wax?

Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
OK, I am running a unported 701 with a factory b-pipe, delta v force reeds, riva intake, dual NOVI 48mm carbs, 13/16 solas concord impeller, lightened flywheel, MSD enhancer, and @ 175psi compression.
I am currently jetted @ 110main 130low 2.3 n/s and popoff is @ 15-20 psi. The highspeed screw is out 1 1/4 and low is 1 1/2. I am loading up on the bottom end. mostly @ 1/4 - 1/3 throttle. It will clear up when I rip on top. I have tried turning in the low spped screw but it gets really lean up top and if I blip the throttle from idle it will stall. I also noticed the carbs are not running the internal fuel filters. Does anyone have any advice on cleaning up the bottom end? Paul sugested to try a 2.0 n/s and raise my popoff. I just want to get some more feed back on this.
 
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tricky1

tricky1

XXX
Location
Alabama
Yes the 48's are a little much for an unported 701. I ran 122.5 low and 135 hi on a ported superstock with 20psi popoff. Good luck getting a crisp bottom end. It prob feels like you have a sock in the pipe.
 
Big Kahuna

Big Kahuna

Administrator
Location
Tuscaloosa, AL
actually, there use to be several Race Limited SJ's that ran 48's, I believe Tera use to use them......... but, I would imagine that she was also running some serious compression numbers also..........
 
W

waxhead

wannabe backflipper
Location
gold coast
i think you are way to large in your carburation and i think the slow airspeed is going to make it always soft down low

However you have to run what you have so lets try to get them going for you

i notice you havent talked about compression ratio
have you upped your compression at all as this enging will most likely need it

i am concerned when you say you have between 15-20 psi pop off as that is a 25% difference, you need to be within half a pound on each carb

like paul says i am agreeing with him
it is soundling like you are to low in the pop off as its sounding like a lean flame out
can you do this for me
get the ski up on the plane and just on the plane so it nice and flat
that will put you in about the low speed jet area
go for 20 secs and then give it a stab on the throttle and tell me what happens
i am suprised your ski will pull a higher popoff but hey stranger things have happened
Do you have a tacho on the ski at all ??
 
Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
Wax, I will try that again but from memory it iwll take a second or two to clear itself out. It seems liek it jsut dumps fuel @ that area. I am going to try and pick yp a real popoff pressure checker today so I can find out exactly what everything is. Thanks for the help everyone.
 
W

waxhead

wannabe backflipper
Location
gold coast
ok make sure as well that your n/s are in good condition
other wise they may be leaking and dripping fuel into the carbs as well
 
matty180

matty180

X-
Location
Mahopac, NY
I ran a the same setup except with a ported cylinder and 205psi. I was running 2.3 needle and seat with a 95g spring. 135 lows and 120 mains. High speed screw was 3/4-1 turn and low speed was 1 1/2 to 1 turn depending on temp. I would guess for a unported cylinder 110 high sounds good. Maybe drop down to a 125 low and put in gold springs to raise your pop off. Also put the stock internal filters back in. Also what size jet do you have in the fuel line restrictor?

Matt
 
Q

QJS

X-
Location
GONE
Paul,
You need to check your fuel pressure with a guage and adjust the return line restrictor accordingly, you should be able to find the instructions for this on Novi's website. Also as Wax says check the needle and seats arnt dribbling, this is very common with large carbs on Superjets due to the low pop-off and high level of vibration at part throttle.
Chris.
 
Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
matty180 said:
I ran a the same setup except with a ported cylinder and 205psi. I was running 2.3 needle and seat with a 95g spring. 135 lows and 120 mains. High speed screw was 3/4-1 turn and low speed was 1 1/2 to 1 turn depending on temp. I would guess for a unported cylinder 110 high sounds good. Maybe drop down to a 125 low and put in gold springs to raise your pop off. Also put the stock internal filters back in. Also what size jet do you have in the fuel line restrictor?

Matt
Click to expand...

I dont have a jet in my return line... Hmmmm....
 
Watty

Watty

Random Performance
Location
Australia
Wax, should the jet in the return line to build pressure be used on stock 46's as well, or is it not really neccessary?
 
matty180

matty180

X-
Location
Mahopac, NY
Yeah, You definitley need the fuel line restrictor in there. Wax is correct, run a 60 mikuni main jet in your fuel line resrtictor. If you dont have the restrictor you can get one from Tim at novi. He is a great guy.

Matt
 
Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
Well, I jsut realized my carbs are 44's the butterfly has 120 on it, however the base hole is 48mm? Well i have been messing around wiht jetting and im getting there. I am at 117.5 pilots 3/4 turn out and 110 mains 1 1/4 turn out with a 2.0 n/s and 22psi popoff. Still rich but i need to pick up some more jets...
My old popoff was 12lbs with 130 pilots, no wonder it was so pig rich!
 
Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
ok, well the 110's are a bit lean up top so I think I might swap them with 115's The bottom end is nice and crisp with the 117.5's at 1 turn out. We will see what happens...
 
Superjet3

Superjet3

Waterlogged
Location
Jersey Shore
OK well it was still lean with the 115's so I went to 125's and it is still lean. I am thinking it is not poping off. I guess I can try lowering the popoff down to 18 or so. any ideas?
 
matty180

matty180

X-
Location
Mahopac, NY
I would put in maybe a bigger pilot. My experiences with novi's is that they always like to have a bigger pilot than main. What exactly is your setup right now?

Matt
 
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