Jetting Advice Wanted

[WaveDemon]

Hey guys,

I upgraded my cases from 61x to 62t during my ski overhaul and am looking for jetting recommendations for dual 44's. Other than the cases and intake manifold this is the same setup I ran before and the ski ran very nice.

I currently have them jetted at
130 low
125 high
2.3 n/s
115g spring
24psi popoff

These carbs are going to be pretty difficult to get off so I'd like to get them close before I get the engine installed.

Specs:
Ported 61x cylinder (was told they were xmetal rec ported)
Ported 62t cases (unknown but are epoxied and have upper corners of the intake area ported. fingers on the bottom of the intake left alone)
R+D port matched intake
stock reeds
Factory pipe Type 9 pipe
180 psi head
MSD enhancer
(2) Yamaha 760 44 Makuni carbs

Thanks!!!!

 

[waxhead]

Thats very simillar jet specs to what I run but your main jet is to big. It will load up mid corner when you gas it. or when cruising then gas it. I run identical with a 110 high. Im going to say to you to run a 115 high. Im on a b-pipe not a type 9. The type 9 will pull harder on the carbs up top so i would think you the 110 is probally closer but to err on the side of cautious go with a 115

 

[waxhead]

Is it the narrow to wide intake manifold you have on the superjet ??

 

[WaveDemon]

Is it the narrow to wide intake manifold you have on the superjet ??

I'm not sure. You tell me - see attached

 

[WaveDemon]

Thats very simillar jet specs to what I run but your main jet is to big. It will load up mid corner when you gas it. or when cruising then gas it. I run identical with a 110 high. Im going to say to you to run a 115 high. Im on a b-pipe not a type 9. The type 9 will pull harder on the carbs up top so i would think you the 110 is probally closer but to err on the side of cautious go with a 115

Thanks Wax. I was trying to error high and started with 120 jets and then installed 125. I guess I went too high! It's good to know I was in the ball park.

 

[waxhead]

I'm not sure. You tell me - see attached

I would find a better manifold if you can

 

[WaveDemon]

my other option right now is a stock manifold with 44 adapters .

 

[fastgtfairlane]

whats wrong with the manifold he has?

 

[waxhead]

whats wrong with the manifold he has?

The way they angle the air/fuel mixture on them loses hp and pushes the mixture all to one side of the reed block. I flow benched one with a smoke machine back in the early days when I was young enough to be compeitive on the race track

 

[tannerwebb]

Thats very simillar jet specs to what I run but your main jet is to big. It will load up mid corner when you gas it. or when cruising then gas it. I run identical with a 110 high. Im going to say to you to run a 115 high. Im on a b-pipe not a type 9. The type 9 will pull harder on the carbs up top so i would think you the 110 is probally closer but to err on the side of cautious go with a 115

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