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Discussion Starter · #1 ·
OK..not sure if I am actually feeling this or its all in my mind. I think under normal acceleration I am feeling a slight surging (the car seems to go fast then slow but vary hard to notice). When I accelerate hard..I feel no surge at all.

So...I have replaced the Fuel Filter (I have one in-line between the Fuel Pump and Carb). Still feels the same.

Could it be a bad Fuel Pump?? (Its the stock Chevy Fuel Pump). Does the 4160 Holley 600 have a brass filter in the fuel inlet and if so could it be clogged? Could the sock in the fuel Tank be clogged some and when under acceleration it has enough flow to make it work better!

BTW - the Engine is a 1969 350, with a 600 Holley, Edelbrock Manifold and Stock exhause manifolds. I have new plug wires, and cap and rotor as well as I took out the stock points and put in an Ignitor Electronic ignition kit.

Any ideas are welcome. I do have a noticable ticking noise which I assume are the Lifters (The car was in storage for 20 years before I acquired it). Could the Lifters be causing the the surging???? or is Surging purely a Gas/fuel issue?? :confused0006:
 

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Your carburetor maybe leaning out, probably an internal issue. Holly's are real easy to work on, if your at all mechanical. First however, I'd check for any vacuum leaks, hoses cracked or loose on the fittings, loose nuts that hold the carb on. Power break booster leaking maybe ? I can't believe it's your fuel pump/filters as you say you have no acceleration problems. Have you checked the timing ? All the basics first need to be looked at. You said the car sat for twenty years, maybe the carb gaskets have dried up and shrunk, causing poor fuel delivery. I'd try enriching the idle mixture screws, to the point that the engine misses. Then drive it and see if there is any difference. That ticking noise you have, carefully put a long rod of some sort on the fuel pump with the engine idling, and see if you can hear if it's the fuel pump or not. If not, you may have a stuck or worn out lifter or even a worn can lobe. You can listen at the valve cover too with that rod, to maybe located which lifter is noisy. From there take that cover off, and inspect the rocker, stud, and push rod. You could try adjusting the rocker first, before any major tear down.

:anim_25:
 

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Discussion Starter · #3 ·
Thanks..will try some of your ideas. I have a complete upper end rebuild ready to go in. New Comp cam (Thumper), lifters, new Valve springs and keepers, and Magnum Rockers. Since I have gfreat power I am sure the lower end is in great shape. Also have a tunnelram and two new Holley 450s to replace the old carb and manifold with. As for the timing I have a new (Loud) Timing Gear set. Also have some fenderwell headers.
Have I left anything out that you can tell might cause me a problem??
 

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I am having the same issue. I have narrowed it down to the carb, although I have had that problem before. Once it was the fuel pump and once the fuel filter. I would start with the 3$ dollar filter then move onto the $25 pump and then the rebuild kit for the carb.
 
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