I installed the new holley 600 carb on my car and it runs ok. The motor shakes in park. No amount of adjustment will take it out. It also stumbles at part thottle. If I am running about 40 miles an hour If I step on it, the car stumbles and then catches up. What could be the adjustment to take this out. I am looking for a smoothe take off and part thottle excelleration.
I had almost that same problem. brand new holley and the secondaries opened too soon. are yer plugs fuel fowled?
I don't like holley's there great carbs but they have 8? adjustments and if any one of them is out there will be a drivability problem.. i got sick of tinkering with mine and put an edlebrock and never had to mess with it again.
Is it New new, or new rebuilt. I have put on new rebuilts that had no adjustment on the mixture screws. Otherwise it kinda sounds like your accelerator pump may be giving you issues. But thats without knowing what your timing is at, if you checked your plugs and wires? did you set your dwell? Whats your base timing with the advance plugged off? When you turn in your mixture screws does anything change as far as are they reacting to your adjustments? Have you checked float level? as you can see there are a lot of things you need to look at.
If you put your hand over the carb and it doesn't stumble you may have an intake leak. Make sure your base gasket is sealing well.
^^^ +1. I would look for vacuum leaks first. or put the choke on partially while driving to see if it stops bogging. if so, it's too lean.
I agree with checking vacuum leaks first. Did you use the base gasket that came with the carb? They are usually too thin, like paper thin. I've used Holleys for many years and have had great success with them, but you will have to tune it for the best performance. My experience has been that they run decent out of the box, better with tuning. Hope this helps!
I checked the plugs they were clean, then I checked the intake for vac. leak none. I have not used a Holley in a long time. I too use the edelbroke. The carb will not run steady it idles wavy.
.Step 1. try to turn idle mixture screws all the way in and turn out 3 and a half turns and hook up va***n guage and then readjust Step 2 .Car off Open throttle plates to full throttle and in wide open position set accelerator pump to 15 thousandths .You'll need two wrenches .Step 3 .Set floats ,While car is running open the two site plugs and make sure no gas is leaking out of carb .You should bump the fender to make the gas trickle out .If you have any problems after that keep us posted .
Also change the back secondary spring in your carb .Spring kit .Stock secondariy spring is way too stiff .Wont open till 5500 rpm .Also check your timing and points . I think its your back float thats the problem .Just a guess.
My first thought was a vacuum leak or possibly something making it run too lean, like dirt in the jets. My 670 CFM Street Avenger has worked perfectly for a year now, right out of the box with no adjustments. 350 Chevy ZZ4 Al
What engine are you running? If chevy,go with the edlebrock performer,In all the years I"ve been turning wrenches,Hollies work good on Fords,CARTER AFB"S on MOPAR,BUT CHEVIES perform better with quadrajets,rodchesters,then EDELBROCK CAME OUT WITH THE PERFOMER SERIES and took the Chevy market .Just my opinion,and we all have that!
Did it run OK right before you added the Holley? Maybe you have an existing problem somewhere else and THINK it's the carb(shaking in Park is a bit weird)? These things are always so damn hard to fix without being there. Is there anything plugged into the big vacuum port that's usually used for the pwr brakes? Cup your hand slowly over the choke horn until you're "almost" completely covered, and see if the motor sounds a LOT better
If you are like me and run a lot of timing advance, And you have a vac*** advance, make sure the hose is on a port with no vac at idle. How far into the throttle before it stumbles?
If it stumbles as soon as you give it throttle, the injector nozzle is too small (go to a .031 or .035). Also if you have cam with a lot of overlap, you will have very little vacuum. Then change the power valve to one that opens later (4.5--5.5). hope this helps you out
Something was wrong with the other carb so We can't go by that. I have a question, when I tune the car up(it's a 350 small block) I changed the va*** advance to one that is adjustable. Do They come in the closed position? If so would this make any difference? I will check to see if we have the dist. conected to the spark port or the continual vac. port. Usually we connect the trans module to the continous port. when the car is cold it will not rev with the choke closed after the car warms it revs nicely.
New carb, timing at 24 total. I did not adjust the accelerator pump yet. HEI dist. Yes it does change when you turn the screws in and out. The float was reset it was a little off.
yes, set the initial timing at 12 degrees advance with the vaccuum line disconnected and see how it idles then.
24 total is way too little. 35-40, depending on compression's more like it. Time it by ear(rotate dizzy counter clockwise). If it sounds happier, re-***ess your total
I like to run 18 degrees initial timing and 36-38 degrees by 3500 rpm or so. Turn your idle mixture screws all the way in and back them out 1 1/2 turns for the initial adjustment on the carb. Like someone else said adjust your floats until the gas trickles out when you bump the fender. You said the engine revs nicely with the choke closed once it warms up? That doesn't seem right at all. Are you sure you don't have a va***e leak? If all that is right it's you accelerator pump adjustment. Most bogs are lean bogs, seems like. I don't understand the Edelbrock carb lovers. Holley's are not hard people, and they perform head and shoulders above the Edelbrocks. I will sugest buying a book for about $22 from Autozone or Kragen or whoever. Holly Tunning Tips and Tricks, don't give up on your Holley, learn it. Good luck and come back and tell us what you figured out please, it will help the next guy.
Ok, 32 total timing. switched the hoses. Dist vac advance to spark timing. The base screws were loose. The vac. advance is adjustable, turned it out three turns and now the car takes off quick. part thottle at 40 mph car pulls out fine. I hit the p***ing gear and instead of chirping it peels tires and holds. Car starts instantly now as well even when cold. Holley is performing beautifully. Idles nice no gas smell. I think we got it thanks all. Kick *** 350.
I knew you'd get to the bottom of the mystery. I have a few pet Holleys that I've used over the years, a 2BBL, 600CFM single pump 4BBL and Q-Jet Spread Bore. I just toss a new kit into them when I resurrect one and I've never had a problem with them. Bob
OK, now, what do you think was the biggest problem from the list above? I'll guess timing. I've started motors to test carbs with NO base nuts. You'd be surprised how HARD a V-8 ****s at idle. BTW-add a couple more degrees at a time and see what else happens. 32 total's nothing for a SBC
Way to chip in fella's. Helping a guy otta a jam w/out him taking it in the short's ta boot! And a bunch of us learned a thing or two about tuning!!
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