Hi, I got a 95 Blaster 1, 61X, 701 that's been board out to 760, 760 head and head gasket, single carb and Factory B pipe. Its got maybe 5 or 6 hours on a new crank and pistons. The other day it scared the shit out of me by stalling at WOT and then turning over really slow. I let it cool down for a few minutes and got it started, went straight home and tested comp, and its all even. I think I dodged a bullet. I'm pretty sure its not running lean cos plug color is good. I'm running parallel cooling ie- single feed from the pump, splits into two, into the manifold and out the head. The water out the pisser is almost too hot to touch. The high jet is 3.5 turns out and I cant make it run rich. I don't know if i'm running too lean and therefor too hot. Do I need to go up a jet size or go dual cooling to fix the WOT stall.
I'd definitely run 2 cooling lines,blasters load up alot more than superjets. What carb jetting,needle/seat/spring do you have ? Sounds like you are running dangerously lean if it stopped on you at wide open throttle.
3.5 turns out on the high? Sounds like the high speed jet is too lean/small. Ideally you would want to be at about 7/8 turn out, max 2. The high speed jet controls fuel delivery till about 90% throttle range, with the screw providing the last bit, what happens when you are that far out and come off a WOT run to 70 or 80% throttle is that the engine is spinning down from max rpm and is faster than what is idea for the throttle setting but the jet can't keep up and it goes lean. But yeah post other settings, and what fuel and compression you have.
Carb is a single minuki 44 High is 150 Low is 110 115gm silver pop off spring There is a 2.0 stamped on the bottom of the needle valve assembly, I assume thats what you mean by 'seat' ? I run 95 pump gas comp is 170
Yeah 2.0 is the needle valve size. I'd wait for Roger (jetwerks) to weigh in, since he has a lot more experience than I do, but my reaction would be to go to 160 at least on the high speed jet. You might need a larger needle valve size too, but I always thought that at least for the 38 SBN's even the 1.5 could flow full capacity.
I would run a 2.3 n/s,same spring 120 pilot 155 main 2 turns out low 1 1/2 out high Pretty hard to tune over the internet,but thats a starting point for you. I'm kickin around Auckland if you need any jets etc or a hand. Cheers Roger 021 148 9711