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Discussion Starter #1
Anyone have comments about Holley 4150 carbs. I set floats Adjusted Fuel pressure.
Cant figure out. Feel like it wiping out cylinders.
 

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is it flooding while running or after you shut down?did you set float levels at bottom of sight hole while idling, no more than 5-6psi fuel pressure, install a filter ahead of carb?
 

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86 vettes normally do not have carbs. If you put carbs in without changing the fuel pump setup you will have waaaaaaay to much fuel pressure for carbs. If you are talking about some other car than your 86 vette you have to be more specific.
 

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Agreed
 

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If your fuel pressure is ok, floats adjusted correctly, then the jets might be wrong, or your engine so out of tune that due to incomplete combustion it can not effectively burn the fuel.
 

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Pressure Regulator

If you're running your stock in-tank electric fuel pump you need to have a pressure regulator in the line just before the carburetor. You can buy pressure regulators from any of the supply houses that sell carburetors. And you also have to have a return line back to the tank as the electric pump will pump way more fuel than your engine can swallow. Set the pressure to 4-1/2 to 5 psi and you'll be good to go.
 

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Also, the stock fuel pressure put out by an 86 fuel system is 34-39psi which will just blow right past the needles and seats in a carburator Your Holley carb setup must have come with instructions regarding fuel presssure, jetting, etc.
 

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Discussion Starter #13 (Edited)
I have a New system for carb. I removed all that stuff. I Have pressure set for about 5 pounds. Problem is. I got a Fuel pressure gauge. NoN fluid type (because when they heat up, They give erroneous readings). But Gauge is gettin fuel in it somehow. I already replaced it and filled with fuel again. I am reading about Holley being notorious for flooding problems.
 

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I have a picture of Bypass fuel regulator. Showing where I installed Gauge. It says to install on side. But I had no room so I put it where plug was. See if you understand.

I think you have it plumbed wrong. I think the pressure port should go to your carburetor's inlet and then there should be a tee in that same line for your pressure gauge. I think the little port you're using (near the adjustment screw) would be connected to the inlet and would show fuel pump pressure.
 

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Discussion Starter #17
Draw what you mean. Plumb is what I was told. By Barry Grant. But Gauge port? is questionable?
 

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Draw what you mean. Plumb is what I was told. By Barry Grant. But Gauge port? is questionable?

I don't know how to post pictures so I'll try to explain it to you the best I can:

1. The inlet port is where you connect the fuel line that is coming from your fuel pump.

2. The return port is connected to the fuel line that goes back to your tank.

3. The pressure port goes to your Holley's inlet. If you want to have a pressure gauge permanently installed you must tee into this line to connect it.

4. I have a feeling the little port near the adjustment screw is where you can connect a vacuum line for some blower/turbocharger applications where an increase in fuel pressure at boost conditions is desirable.
 

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Discussion Starter #19
That would make sense hopefully. But when I look at PRessure port, I can see that hole clearly. Thought it would be same pressure? That hole shares same chamber.
 

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Is this a new carb? While I think it is likely a pressure problem...It is possible that your flooding has nothing to do with excessive pressure or the floats.. a blown or incorrect rated powervalve will let fuel dump in when engine is not requiring it...Holleys are really very simple in design and usually very reliable for years.
 
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