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- Posted: Thu, 16 Feb 2012 18:42:45 +0000
Lol. Right. Well, if you need any help, I'll be sure to not help. I'm going to stand on the sidelines with a bag of chips and laugh.
The Jolly Douche bag
it's a holley duel feed double pumper, and i just go to the good ol' car quest right next door and order a rebuild kit, and the i do what i be do
If you don't understand how they do what they do, then how would you know which Holley power valve to use? which air bleeds, jets, floats? What the correct fuel level is in the bowls? Do you even know WHAT carburetor it is? I only assume it's a Holley, because Vettes always had Holleys.
The Jolly Douche bag
i know what i'm doing i just dont understand how they do what they do
First off. What kind of carb? I assume because it's a Corvette, it's a Holley. If it's a Holley, WHICH holley? First off, why are you rebuilding peoples' carbs if you have no idea how they work?
You're an idiot. I'm sure you were born with all the knowledge in the world crammed into that thick head of yours. The guy has a question answer it or shut the ******** up.
He's rebuilding, meaning he gets the carb model and a rebuild kit for it. He isn't tuning for maximum power meaning he won't need to select floats, air bleeds, jets, or power valve(assuming it's good, either way you tell the carb model and BAM). Learn the meaning of the word rebuild. But to help you understand, a rebuild is gaskets, seals and cleaning. Modifying is selecting different individual parts. He isn't trying to make it run hi-numbers, he's making it work again to factory standards.
And by the way, depending on the year the Corvette could have had a Quadrajet Rochester or a C1 Carter as well. Also how is it possible that only Corvettes had 'bad Holleys' considering the Z28 Camaros, BBC Chevelles, Shelby Mustangs, and Boss Mustangs were also Holley powered? I suppose it it was just the Corvette logo on the car... The 2bbl Holleys used on the triple deuce set up of the CORVETTE 427 are highly sought after because they are such good carbs. Do you know what YOUR talking about? Here's a good question, what would you do if you had a carb fire while the engine is running?
ANYWAY, to the question.
Naturally fuel starts in the tank, brought through the filter by means of the pump yada yada. The fuel is pumped into the bowls through the needle-and-seat assembly, and then drawn into the intake through the pressure differential. The carburetor's venturi increases air speed in the section where it necks down, creating a low-pressure area. Because of this lower air pressure that enables fuel to be pushed from the fuel bowls into the intake manifold. Also, boosters in the venturi, which act as a venturi within a venturi, further increases the pressure drop without significantly compromising airflow.
Now, for the fuel droplets that would be too large for effective burning without a means of introducing air into the mix, that's where the air bleeds come in. Tubes carry fuel from the fuel bowls to the venturis and preatomize the fuel by mixing it with the air through said air bleeds.
The Float works like a float in a toilet... actually the whole carb kind of works like a toilet... anyway.. When the car is at idle the bowl is full, the float is up and the fuel supply is restricted. When the car is running like a sane human being the float drops with the fuel level in the bowl, the fuel supply to the bowl is opened up based on float position. The float moves up and down based on throttle position and fuel level inside the bowl. The float is constantly maintaining balance inside the bowl metering how much fuel is allowed into the bowl and the engine's supply. So it's kinda of like... Float Up-engine idling- minimal amount of fuel entering bowl. lets say...90% restriction
Float in center of travel-Engine is loaded- 50% of possible fuel is entering bowl. 50% restriction
WOT Float is at bottom of travel - unrestricted flow into the bowl- 0% restriction.
Float level is critical in tuning. Too high and you'll starve the engine at idle, too low you'll oversupply the engine. Either flooding in extreme cases, poor power and fuel economy, carb fires in cases.
Carbs aren't as scary as they sound, and it's not witchcraft that makes them work... Though Demons are damn good (bada ching). Don't over complicate it and you'll do fine.