I have a chevy 350, new edelbrock 600cfm carb, new fuel filter, and a mild cam. When the engine is at idle and cruising it is fine. When i push the pedal to the floor it acts like it is running out of gas. It stumbles and doesn't recover until you let off of the gas. What could be causing it to fall on it face?
2007-10-13 12:37:27 · 11 answers · asked by danthegeek 1 in Cars & Transportation ➔ Car Makes ➔ Chevrolet
I have a chevy 350, new edelbrock 600cfm carb, new fuel filter, and a mild cam. When the engine is at idle and cruising it is fine. When i push the pedal to the floor it acts like it is running out of gas. It stumbles and doesn't recover until you let off of the gas. What could be causing it to fall on it face?
I have tried ajusting the timing with no change. I have a clear fuel filter and it seems to suck the fuel right out when I rev the motor. Could I have a bad fuel line (has a new gas tank)?
2007-10-13 12:47:09 · update #1
you need to re jet this carb. I have seen this a hundred times. start with the jets you have. remove the top of the carb. I assume you know what to look for. switch the back 2 jets with the front 2 and your problem will go away. Good luck.
2007-10-13 14:59:46 · answer #1 · answered by rodneyj 3 · 0⤊ 0⤋
"I have tried ajusting the timing with no change. I have a clear fuel filter and it seems to suck the fuel right out when I rev the motor. Could I have a bad fuel line (has a new gas tank)?"
Sounds like you need a better fuel pump or bigger fuel line. Maybe both. 7/16 fuel line and an electric fuel pump should fix it. Another thing to check for is a partially clogged exhaust system. This can also cause your stumbling problem.
2007-10-14 15:07:47 · answer #2 · answered by monte 6 · 0⤊ 0⤋
Could be a number of things...do you get lots of black smoke from the tailpipe or not?---sounds like the carb fuel enrichment circuit is not set up right which could be caused by an improper/faulty accelerator pump or linkage to it or nozzles, could be from a bad power valve not set up for the vacuum you are pulling---you'd have to hook up a vacuum gauge at idle to see what you're pulling and get a power valve a couple steps lower, could be a vacuum secondary not opening correctly or prematurely causing a bog from too much air flow, could be jets are the wrong size but not likely if it runs good otherwise. There are many factors in tuning an aftermarket carb to your specific engine characteristics...best to buy a carb tuning manual and read up on what factors affect the performance. You can spend hours tinkering with adjustments so it's best to have an idea of how the various carb circuits work. Engine timing and advance is important too...they all have to work together with the carb settings.
2007-10-13 15:57:58 · answer #3 · answered by paul h 7 · 0⤊ 0⤋
Check the acelerator pump linkage on your carburator... it must shot 2 streams of fuel down the venturi the instant you move the linkage... these are normaly adjustable and will have to be fine tuned to spray at the instant the throttle plate opens... this is your fuel enrichment... if it does not work properly your car will fall on its face when you step on the gas.... set your total advance at no more than 38 to 40 degrees at approx 3000 rpm this will allow your 5.7 to perform at its peak hp and torque... too much advance will kill your hole-shot... good luck
2007-10-13 15:05:57 · answer #4 · answered by RiverRat 5 · 0⤊ 1⤋
My bet would be the wrong jets in the carb. I put a holley on one of my cars back in the 70's, it was supposed to be set up for my small block, but my car did exactly what yours is doing. I pulled the jets, checked the book and found they were set up for a big block.
2007-10-13 12:50:52 · answer #5 · answered by randy 7 · 1⤊ 0⤋
Open the choke manually so you can look down the throttle,use your hand to pump full stroke the accelerator a couple times,should see fuel shoot down from the top jets,near the choke butterfly.That is your accelerating fuel.
2007-10-15 12:47:19 · answer #6 · answered by CarmaNguyen 7 · 0⤊ 0⤋
Is your float adjusted correctly? Do you have enough of a pump shot to overcome the momentary change in air speed velocity? If you enrichen the mixture does it help?
2007-10-13 12:51:13 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Your float may need to be adjusted in the carburator or perhaps the metering jets.
2007-10-13 12:50:48 · answer #8 · answered by Fixguy 5 · 0⤊ 0⤋
The initial timing may be off or the distributor advance may be defective.
2007-10-13 12:43:47 · answer #9 · answered by Otto 7 · 0⤊ 0⤋
timing could be off
Try advancing the timing a few degrees
2007-10-13 12:41:25 · answer #10 · answered by mike h 4 · 0⤊ 0⤋