I was told that with all my mods (Toomey T-5's, v-force reeds, wisesco pistons .020 over, low-mid porting, intake porting, noss head, 20cc domes, 2 into 1 keihin 35mm carb, and k&n filter) that I need to increase the timing. Do I need to? I was also told that the carb won't work right unless I get a fuel pump and new reeds. The carb has a power jet, and thats why the guy said I would need a fuel pump and new reeds. Is there a way to shut off the power jet? This is from his email: "power jet carbs suck you will not be able to keep the bowl full unless put in a 2 psi electric fuel pump when you go full throttle back off hit it agian, blows too much fuel then leans used these back in the 70s and they have not changed still suck, they put fuel in or lean it they are very inconsistence for air fuel ratios". Is any of that true? I am totally lost here, I've had 3 different people tell me 3 different things about jetting and this guy is telling me my setup sucks and it wont work. What should I do?

 

My only experience with power jet carbs was on mikuni flat slides used on the first two years of Ski-Doo's 800cc mach z triple. Ski-Doo never could get it dialed in consistently with the power jet set up. Not sure if you're clear on how they work, but they add an extra "power jet circuit" that only gets gas when the throttle is held open for longer periods of time, thus allowing a leaner main jet for times when only brief wide open throttle settings are needed. They are finicky, as even the length of power jet hose effects how they work. Anyway, Ski-Doo came up with an update on the second year that included disabling the power jet by simply putting a blank jet (no hole) in the power jet circuit, then richening up the main jet. To my knowledge, no sleds (the state of the art in two strokes right now) uses this device.