Ok....i would like to post a vid of my car to have someone help me out.. My carburetor on my 69 impala wont keep a constanst idle,, short of running out and buying another 300 dollar carb...i would like to get this one runningsmooth again.....when i crank the motor it starts with a pump of gas but then its rpms are super high like 1500-2000... then it acts like its going to idle then ..kput.. it dies and i gotta start it again... what is causing this non idle senerio? i dismanteled and cleaned the carb 4 times.....still rough or no idle....

 

welcome to TR . I moved your question for tech help to the correct forum

thank you

chi town brat
S Mod

 

check the cap and rotor. if it checks out ok then pull the spark plugs and see if any are fouled out. if thats all good then go after timing. also check your mixture on the carb. sounds like either the floats are too low or too high. either way could make this happen. good luck and let us kno what ya find

 

^+1

 

pretty much on the spot, but the only other thing i would suggest is see how the car runs once it has warmed up if you can get it to.

the idle issue seems more of a timing problem so get a timing light on it and see where its at and work from there.

 

I have a 71000 series accell breakerless electronic distributor and an accell super coil...so its not cap and rotor issues...its not timing...timing is 0degrees TDC, i guess i could advane it a little but it is not the problem...sucker starts and runs but idles high....i saw a vid from edelbrock that suggests it might be a vacuume leak around the carb...i'll check that today....if it doesnt work..i'll go to advance and get another carb then take my bad one back and get my money back....so i'll tell you all later if its a vacuume leak or not..

 

.......0 degrees of ignition timing would be your first issue......go ahead and turn it to 10*BTDC and see how she does...changing the timing can affect the idle rpm. sometimes people mistake that for the idle air screws as far as the proper way of adjusting idle rpm..

 

^+1 that would be the problem. 10 degrees should be good. youll find itll cool better too.

 

Deacon... i really dont think you know what you are talking about.... i have always kept the timing at 0 degrees..only when i race do i change it up to 10 degrees advanced for more power... timing at TDC has never given me a problem....its the carb...i screwed in the air fuel mixture screws all the way which should raise the idle even more.....it didnt....i backed them all out almost all the way....still no change.....I am cleaning up my Demon 750 and gonna try that carb...I have never had an issue with idleing at 0 degrees...so i have no clue what or if you even know hw to tune carb cars....i need someone with experience ....like me......to help...not an import computer tuner..

 

i think, if you found someone with experience, like you....you'd still be in the same situation, and wasting twice as much oxygen.

will a car run at 0* timing, eh maybe, but pretty shitty. currently i am at a loss to think of any engine equipped with spark plugs that does not fire before TDC. for the simple reason the chain reaction of igniting the fuel doesnt happen instantaneously...im not going to go on a timing rambling or how the flame front travels and how the stroke gains or loses efficiency...i am just going to tell you, running 0* of timing is not what it is supposed to be at...especially a SBC...hell, i am not even going to ask how you worked out that special number of 10* advance for more power, cause i can probably go ahead and say its just some wild ass number someone pulled out of their ass.

anyways.... the typical way of setting up your carb is idle the engine till its warm, adjust the idle speed screw to an rpm suitable for your setup, i needed mine at 1000, but i had a somewhat big cam, if your stock or close to it, ya only need to go around 800 or so.

and by what you wrote in what i quoted, it sounds like you don't know what the idle mix screws are even for. so go get a vacuum guage, plug it into your manifold, and with the car running mind you...and warmed up...turn them all the way in and back them out 1/4-1/2 turn at a time..backing each out equally. do that until you get the most vacuum possible from the guage...we do this so those snazzy little things that slow your car down, work.

when you get done with all that let me know how it turned out, till then, im going to go put the new tune on my intake and exhaust integra