Paddiee

So I have a Holley Model 4160 Non-Adjustable Float Carburetor: 600 cfm 4 barrel. I was looking at the rear bowl and when I took it off, there was some sort of block plate there. The rear inlets that dump fuel into the carb are bone dry.. I've had the carb for 3 months now and I just noticed this. When going full throttle, the rear flaps of the carb that let in air don't open. I'm not sure exactly what the situation is, but I'm only using half of the carburetor. There are no jets in the back bowl, just a float. I know very little about carbs but the only area where fuel is going into the engine is under the choke flap.

http://www.summitracing.com/parts/HL...457S/?rtype=10

Apeiron

You won't see the secondaries open on a vacuum secondary carb when you just blip the throttle from idle.

Paddiee

Did not know that. When I was playing with the linkage for the secondaries, they were very tough to open almost like they were seized. Is fuel meant to go into the engine from the back 2 inlets? There were no jets or ports for fuel to go into those. If they don't work, what are they for?

Apeiron

The secondaries are vacuum operated, they'll only open when there's flow to produce enough ventury vacuum to open them.

There are ports in all 4 barrels. What you're calling "jets" in the primaries are probably really the accelerator pump nozzles. There aren't those in the secondaries.

Paddiee

Ooooooooooh I see.

lowridetractor

iTrader: (2)

also when you have the rear bowl off, that plate is call a metering plate. most vacuum secondary hollys have them instead of jets.

Paddiee

Ok I see. Question, stepping on the brakes would stall out my car. Given the carb I have, what issues with it would lend that to happen? What I did to fix the problem itself was open the choke all the way so it breathes with no restrictions. I don't know if that was the real solution to the problem but it doesn't sputter out and die on me anymore. I had both bowls off and fuel was getting to the engine just fine but for some reason, the engine was getting flooded...I think...and dying on me. It would take a good 5 seconds of cranking to get it started again. The car was leaned out but I don't know if that would cause it to suddenly die. Strictly carb-related, what kinds of things with the carb would make a car die while braking?

InfernalVortex

iTrader: (4)

Sounds like you need to learn to tune carburetors... It's not as bad as you may think. You just gotta play with it for a while.

Do you have a stock engine or do you have an engine with a lumpy cam? If a lumpy cam... do you have the factory stall converter? If so it could be dragging a little to make your car want to stall under deceleration. Had a friend that had a problem from that.

But it could be anything. The choke flap should be ALL THE WAY OPEN when the engine is warm, or else it will fuel the engine overly rich. This could also be the cause. It should only be partially closed when the engine is cold and not up to temperature yet.

Paddiee

Yeah I definitely should learn haha. The cam I have is very mild. Its practically stock. I opened the choke flap all the way and it stopped dying on me.