Carb tuning. help me! FOR THE LOVE OF GOD HELP ME!

[84Z28]

Ok heres the scoop. I have a Carter AFB competition series 4bbl carb, dont know what CFM it is.. it came with the car. Anyways, i think it is out of tune or something. When i drive the car for like 20 minutes or something (when its warmed up), if im at a red light or something and i hit the gas in first second or third it makes this HUGE popping noise! I know it is coming from the carb, i can tell. The car pops and it like.. slows down for a second and then goes fast again...? If that makes sense. There are 2 needles on the front of the carb that may be used to change the air/ fuel mixture? I have never touched them because i was scared that if i turned them i would fuck it up even more.. please help me!

[CamaroRobZ28beer]

They should be all the way in, then like 2 and a half turns out, but dont touch them, It might be back firing through your carb because of your timing.

[84Z28]

so i should get my timing checked first?

[talos]

Check this website (http://www.bob2000.com/carb.htm) out, it helps alot when ur trying to turn ur own carb...

fyi basic stock timing should be around 8 degrees.

[84Z28]

uhh whats the website

[talos]

click on the word "website"

[84Z28]

::)

[79 Z28]

click on the word "website"
buhahaha so devious, :P

[84Z28]

i hate fucking with my carb.. i guess i could just put a mark where it is now and just turn it where ever i want then put it back to the mark. its really gay when i am at a light, i try to show off and pin the gass and it fucknig explodes. i feel like such a loser

[84Z28]

>:(

[talos]

"My engine is backfiring at idle"
Symptom - Backfires through carburetor

Remedy - A) With the engine running, open idle-mixture screws located on the sides of the metering blocks. Open and close the throttle, if backfire continues, turn the idle-mixture screws out until the problem disappears.
Try this next if this didn't solve the problem

B) Increase squirter size. The squirters are located above the primary and secondary venturi bores. These are retained by a screw and feed the carburetor the initial shot of fuel when the accelerator is depressed. Consult your Demon instruction manual for the standard size. BG Fuel Systems offers a wide range of squirters that are available at your dealer. Go up one size until the problem is cured.
Try this next if this didn't solve the problem

C) Increase jet size. Drain the fuel from the float bowl and remove the float bowl. This exposes the metering block. The jets are two brass screws with holes in them at the bottom of the metering block.

Remove the jets. Once the jet is removed, you will see a number stamped on the edge of the jet. This is the jet size. Go to your performance parts dealer and purchase genuine BG Fuel Systems Service Parts 2300xx-series jets (xx is the jet size from 50 to100). Look at the jet size that is in the carburetor's metering block and go up from there in one size increments.

Try this next if this didn't solve the problem

D) Raise float level by loosening the set screw on the needle & seat assembly and then turning the nut counterclockwise (to the left) until the backfire stops. The fuel level in the float bowl sight window should be initially set at the middle marker line.
Try this next if this didn't solve the problem

E) Check ignition timing. The engine's initial timing should be between 18 and 24 BTDC (before Top Dead Center). Use a timing light to establish the correct timing setting.

[talos]

"My engine is backfiring under acceleration"
Symptom - Backfires through carburetor

Remedy - A) With the engine running, open idle-mixture screws located on the sides of the metering blocks. Turn the screws counterclockwise ¼ turn. Open and close the throttle, if backfire continues, turn the idle-mixture screws out ¼ turn at a time until the problem disappears.
Try this next if this didn't solve the problem

B) Increase squirter size. The squirters are located above the primary and secondary venturi bores. These are retained by a screw and feed the carburetor the initial shot of fuel when the accelerator is depressed. Consult your Demon instruction manual for the standard size. BG Fuel Systems offers a wide range of squirters that are available at your dealer. Go up one size until the problem is cured.
Try this next if this didn't solve the problem

C) Increase jet size. Drain the fuel from the float bowl and remove the float bowl. This exposes the metering block. The jets are two brass screws with holes in them at the bottom of the metering block.

Remove the jets. Once the jet is removed, you will see a number stamped on the edge of the jet. This is the jet size. Go to your performance parts dealer and purchase genuine BG Fuel Systems Service Parts 2300xx-series jets (xx is the jet size from 50 to100). Look at the jet size that is in the carburetor's metering block and go up from there in one size increments.

Try this next if this didn't solve the problem

D) Raise float level by loosening the set screw on the needle & seat assembly and then turning the nut counterclockwise (to the left) until the backfire stops. The fuel level in the float bowl sight window should be initially set at the middle marker line.
Try this next if this didn't solve the problem

E) Check ignition timing. The engine's initial timing should be between 18 and 24 BTDC (before Top Dead Center). Use a timing light to establish the correct timing setting.

[84Z28]

It isnt backfiring at idle. its when i floor it after the car has been running for a while.

[talos]

then read the other post about backfiring under acceleration.

[84Z28]

oops hahah. i thought that it was a double post. I dont have a demon carb.. or holley for that matter... its ocmpletely different.. isnt it

[talos]

sure the designs are different, but they work under the same prinsables(sp?)

[84Z28]

its principles (i think)

So i went out and turned the car on and turned the needles.. nothing seemed to happen. . so i put them back to where they were. anyone going out to get pissed tonight

[84Z28]

ok now its doing it really bad.. i was driving down the highway in 5th gear, i pushed the gas a little harder and it just fuckin popped away. POP OPOPOPOPO PO POPO P pp p p p p p PO POPOPOPOOP and then i let off and it goes away.. im thinking it isnt getting enough fuel to the carb.. how much for an electric pump?? i have the stock mechanical one right now

[79 Z28]

check fuel kinks, fuel filter, tank lines, etc etc. i got a holley pump for sale, its great, but youd need to buy a 40 dollar regulator for it, but its good for 500hp ;D

[84Z28]

is it hard to hook up?? I think it could possibly be the fuel filter.. it has probably been on the car for like 4 years.. maybe 5.

[79 Z28]

its a mechanical pump, a retard could do it, thats how hard it is ;D

[84Z28]

how much?? and whats a regulator?

[79 Z28]

how much?? and whats a regulator?
im asking $70 its practically brand new, paid about 145 after tax for it. a regulator regulates fuel pressure, this pump puts out about 14psi way way too high for a carb alone to handle, the regulator is adjustable and should be set around 5 psi for most carbs. so thats what its for :)