CarburetorsCarb discussion and questions. Upgrading your Third Gen's carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
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It's a lean condition. It doesn't have anything to do with the accelerator springs (at least, certainly shouldn't if the carb was "professionaly built" - did you fiddle with them after they put it together?). You aren't getting a sufficient accelerator pump shot, which means the mixture is going to be lean until the main fuel circuits can catch up.
It also doesn't have anything to do with fuel pressure. Fuel pressure merely fills the fuel bowls, it doesn't directly affect lean or rich. However, float level could affect you, so verify the fuel bowls are being filled to the proper level.
"Professionally building" a 750 so it flows 925 CFM is a stretch. You can do that by fudging a few things, like the vacuum level at which you measure the flow (although I doubt they actually did a flow test on it), but I'd be very suspicious of anyone who claims they modified a 750 to flow 925 CFM. Did they give you a build sheet? Do you have information such as jet sizes, power valve #'s, accelerator pump volume, squirter size, air bleed modifications, etc.?
It's a lean condition. It doesn't have anything to do with the accelerator springs (at least, certainly shouldn't if the carb was "professionaly built" - did you fiddle with them after they put it together?). You aren't getting a sufficient accelerator pump shot, which means the mixture is going to be lean until the main fuel circuits can catch up.
It also doesn't have anything to do with fuel pressure. Fuel pressure merely fills the fuel bowls, it doesn't directly affect lean or rich. However, float level could affect you, so verify the fuel bowls are being filled to the proper level.
"Professionally building" a 750 so it flows 925 CFM is a stretch. You can do that by fudging a few things, like the vacuum level at which you measure the flow (although I doubt they actually did a flow test on it), but I'd be very suspicious of anyone who claims they modified a 750 to flow 925 CFM. Did they give you a build sheet? Do you have information such as jet sizes, power valve #'s, accelerator pump volume, squirter size, air bleed modifications, etc.?
Alright ya the i changed an intake from the rpm air ap to a vitctor. so we changed the a/f screws and i think myaccel pump springs are of some.
They gave me a build sheet and everything.
Its a 900 dollar carb, i get perfect gas mileage and literally gained hp just from swapping it. they bored out the carb some too and all.
They have 80's all around for jetting whch they gave me 78's originally
No power valves, or PV's both primary and secondary?
What size are the accelerator pumps and squirters?
Are you running a Victor or Victor Jr.? Single plain intakes will reduce the vacuum signal to the carb, requiring more accelerator shot to make up for it. Did this only start after the intake change? You may also have a vacuum leak.
