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Discussion Starter · #1 ·
i have a holley model 4160 1850-3 600cfm and i just threw it on my 72 nova to see what it would do if anything. it idled fine but when i went to turn the adjuster screws it wouldnt do anything. where do i go from here? when i revved it quick it would stumble for a real quick second then pick back up. i couldnt take it out too much rain to really do anything. i have had problems from before with it but i rebuilt it this time around and sprayed averything out with carb clean and blew it out with air. is my metering block in need of help or should i give the mixture screw holes a good shot of carb clean?
 

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If your idle mixture screws are non-responsive, that usually means you are idling on the transfer circuit. You need to close the primary throttle blades to get it to idle on the idle circuit; and maybe you need to open up the secondaries to get it to idle.

Where is your timing set at?
 

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I think you need more initial, at least 16. Doing that will raise your idle speed. Then you can adjust the curb idle screw down and that will let you adjust your mixture.

If you have vac advance, connect it to the port in the base plate, not the one in the metering block.

Squirter pump shot can cause an off idle bog, but before playing with that, you need to get the idle mixture right.
 

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YUP,JUST WHAT ZEKE SAID,but if you running any kind of aftermarket perf cam you would likely need a few deg more base timing then 16 which isnt bad but 18 is better.

But the 12 deg base timing your currently at is approx 6 deg retarded which is substantial.

When setting base timing ensure idle is 600-650 rpm to ensure mech adv in the dist isnt partially activated goofing up base timing adj. Also remove the vac adv & plug it when setting/checking base & total timing.

Then after setting base timing to 18 rev the motor (with vad adv still plugged/unhooked)
to 3k rpm where your looking for approx 36-38 deg total timing at most.

If total is over 38 by only a couple deg then back off the base timing that 2 deg and your good to go. But if total is more then a couple deg over 38 then you must have the mech adv recurved for 18 deg in by 2800-3k rpms.

But dont just retard the total timing over a couple deg to get it back to 38 or 36,thats because foe every deg you retartd the total timng your also retarding the base timing and you end right where you started with retarded base timing when you do that.

So now with 18 base + 18 mech adv in dist you will have 36 total which is a good place3 to start.

Dont forget to re-attach vac adv and also reset idle speed & mixture post timing adj.

Good luck.

Scott
 

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Shoulda called me!!!
I seldom look here figuring pals in trouble would call or PM me.....
 

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Discussion Starter · #10 ·
see i figured somethin was retarted with it haha. i was out there for about an hour and it i just dont want to play with it anymore. it would idle at about 1100 for about 30 seconds and then come wayyyyy down and die. i couldnt even get any timing done on it with the holley on. the floats are adjusted properly i ran it and turned it off at 1100 and the fuel was whre it should be in the bowl. even when it died it was at the same level. the mixture screws still had no effect whatsoever. this is how the carb always was for me. it sat on my uncles shelf for a couple years and i rebuilt it, never got it quite right then it sat on mine for 3. ill just stick my edelbrock back on till i decide to get a new one. i was going to use this for the tow rig i will be purchasing so i may try to slap it on the truck (67 chevy 2wd longbox with a towing gear 4 speed and a 283) and play with a little more room under the hood but only till i throw it down the road haha
 

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You should not try to set base timing with motor idling at 1100 rpms,that will likely cause the mech adv to activate in dist resulting the retarded base timing.

You should set base timing with the motor idling ow like 600-650 rpm,not 1,000-1,100 rpm,too high.

Did you have the vac adv unhooked when trying to set base timing because if it was hooked up that could have been what what caused the ilde to be unstable along with the mech adv in the dist slowly backing off resulting the idlin speed dropping off.

Scott
 

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it would not idle at 600 rpms so i could not set timing. the vac adv was unhooked. the carb is a lost cause for me
Drive it down and I'll help you.
 
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