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4 corner idle VS 2corner circuit adjustment #1054865 08/17/11 04:32 PM 08/17/11 04:32 PM
Joined: Feb 2011 Posts: 145 B.C. Canada H hankcrank OP member
hankcrank OP member H Joined: Feb 2011 Posts: 145 B.C. Canada	I have read many posts on the idle mixture screw adjustments on Holley carbs.I read 1-1/2 turns out for a starting point on all carbs. I have read 3/4 turn out for a starting point. I have been told from cab. experts 1-1/2 turns out on a 2 corner carb. and 3/4 turn out on 4 corner idle circuits. Does anyone know for sure what is the right amount of turns for a starting point? 3/4 to 1-1/2 is quite a difference.

Re: 4 corner idle VS 2corner circuit adjustment [Re: hankcrank] #1054866 08/17/11 05:39 PM 08/17/11 05:39 PM
Joined: Jan 2003 Posts: 1,022 Andrews,In. U.S.of A. 6 67_Satellite super stock
67_Satellite super stock 6 Joined: Jan 2003 Posts: 1,022 Andrews,In. U.S.of A.	A starting point is just that. You're going to adjust it up and down anyway. If it starts with the screws 3/4 turns out, and runs long enough to make your adjustments,it will be o.k.

Re: 4 corner idle VS 2corner circuit adjustment [Re: hankcrank] #1054867 08/17/11 06:03 PM 08/17/11 06:03 PM
Joined: Aug 2003 Posts: 43,228 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,228 Bend,OR USA	I would tune it to make you happy I like and use from 1/4 turn to 1 full turn on most of my motors with big cams idling at or under 1000 RPM, I do open the idle bleeds up to help lean the idle circuit down also I like to see from 14.5 to 15.8 AFR on my wide ban, that does make it cold blooded to start when cold but so what Lean is mean Now if I can get the part throttle near 14.0 or above I'll be good Another thing to use on tuning the idle circiut is to stand at the rear or side of the car where the exhaust exits and smell it, if it is rich you will smell it, if it is not rich it won't stink as bad, even with good smelling race gas One other last thing, if you can start the car cold and it idles right away your probally on the rich side on the idle circiut Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 4 corner idle VS 2corner circuit adjustment [Re: hankcrank] #1054868 08/17/11 06:25 PM 08/17/11 06:25 PM
Joined: Nov 2003 Posts: 6,293 Rock Springs Bob_Coomer master
Bob_Coomer master Joined: Nov 2003 Posts: 6,293 Rock Springs	Quote: I have read many posts on the idle mixture screw adjustments on Holley carbs.I read 1-1/2 turns out for a starting point on all carbs. I have read 3/4 turn out for a starting point. I have been told from cab. experts 1-1/2 turns out on a 2 corner carb. and 3/4 turn out on 4 corner idle circuits. Does anyone know for sure what is the right amount of turns for a starting point? 3/4 to 1-1/2 is quite a difference. No one can say what your engine will like.. Every engine is diff. Cam size plays a roll, way to many variables. If your interested in learning how to properly tune your engine, get a base line and start making changes... Only one change at a time though... [color:"red"]65 Hemi Belvedere coming soon [/color] [color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]

Re: 4 corner idle VS 2corner circuit adjustment [Re: Bob_Coomer] #1054869 08/17/11 09:14 PM 08/17/11 09:14 PM
Joined: Jun 2010 Posts: 469 Tennessee S steeldust mopar
steeldust mopar S Joined: Jun 2010 Posts: 469 Tennessee	Quote: Quote: I have read many posts on the idle mixture screw adjustments on Holley carbs.I read 1-1/2 turns out for a starting point on all carbs. I have read 3/4 turn out for a starting point. I have been told from cab. experts 1-1/2 turns out on a 2 corner carb. and 3/4 turn out on 4 corner idle circuits. Does anyone know for sure what is the right amount of turns for a starting point? 3/4 to 1-1/2 is quite a difference. No one can say what your engine will like.. Every engine is diff. Cam size plays a roll, way to many variables. If your interested in learning how to properly tune your engine, get a base line and start making changes... Only one change at a time though... I AGREE 100% YOU ARE RIGHT BOB. 6783070-JUNEBOUNTYRACE.jpg (122 downloads)

Re: 4 corner idle VS 2corner circuit adjustment [Re: hankcrank] #1054870 08/18/11 06:26 PM 08/18/11 06:26 PM
Joined: Mar 2007 Posts: 3,285 West Coast, USA jbc426 master
jbc426 master Joined: Mar 2007 Posts: 3,285 West Coast, USA	Given that the timing is set correctly, the air bleeds are properly sized and throttle blade position at idle is covering the correct amount of the idle transfer slots, I run them 1/2 to 3/4 of a turn out from lean mis-fire. Screw them out just until the idle will no longer increase, then screw them back in until it starts to lean mis-fire (idle decreases) then back out 1/2 to 3/4 of a turn. Go around until they are all consistently 1/2 to 3/4 of a turn out from lean mis-fire. it may take several times to balance/stabilize them. 1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's 1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)

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