ok i got a holley 4160.....after my cam swap i had to bump my timing quite a bit to the advance side to make it run smooth,..now my engine idles a lot higher....about 1100 vs. 850 or so...can this be from advancing the timing....no matter how much i mess with the idle screw or the mixture screws it doesnt change....it is fairly normal though once i put it into park.....also it is running really rich and it wont lean out at all....i even tried it with the screws all the way in....also could my electric choke i put on be causing any of this....right now i have it turned so it doesnt even use the choke......i dont get reallt how the fast idle cam and the lil thing with the bumps work on the electric choke but i think it is together right.......i havent used it much with the actual choke on but when i did it didnt seem to want to come off.....i know this is all kinda jumbled but if you need me to elaborate just ask

 

Note that my experience with carburetors is fairly limited - my suggestions come as much from a theoretical understanding as real world experience. Take them for what they're worth.

If the you can't make the engine slow down, you have a vacuum leak somewhere. I can think of a couple places to check:

Something might be holding a throttle plate open - it could be the fast idle screw and cam are misadjusted, or something is binding. Also check the secondary idle setting - it could be holding the secondaries open enough for the engine to run on the secondary main circuit.

You could also have a vacuum leak somewhere else - you could check the usual suspects.

Realy rich running could be a lot of things. My guess is that you have a throttle plate open and the carburetor is pulling fuel from the main circuit rather than the idle circuit - that would explain why the idle mixture screws have no effect.

You could also disable/remove/whatever the choke and fast idle cam - that way you can be sure that they're not involved; it'll be easier to get things working without worrying about them.

 

VERY good assessment for limited experience!
I'll second that.

 

ok so first tear off the coke and the fast idle cam and hold the choke open....see if the idle is still being funky......try searching for a vacumm leak....and if it is the main circuit thing....could that be whats causing me to get very low gas milage....i know its a holley but it uses up a full tank sometimes in less than 75 miles

 

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Naw man leave the coke on the car and mess with the choke. Just messing.

The first question, yes advancing the timing will increase RPM. I doubt the carb gasket or any acs's are leaking because you would hear wisling and have a lean out problem not rich. What number is stamped on the choke tower? an 1850 is still a 4160 series and has counter clockwise screws with blunt tips, standard clockwise have pointed tips. 99% of the time a blown power valve will do all you describe or high float level. Just as long as holley put a metering plate in your carb you should be able to fix it, lol enough of my problems. Fast Idle adjustment can also cause a rich problem but if it ran before I would shoot for power valve or float level somthing likely to get blown out of whack durring a cam swap.

 

im just gonna pick up a rebuild kit while i have it off and go at it...floats seem complicated so i wont mess with them unless this stuff dont fix it

 

You'll have to reset the float level anyway when you rebuild the carburetor. They're not very hard at all to adjust.