idles smoother at a lower rpm (cold start, no choke)
12-15-2001, 12:56 PM
#1
Race Director
Thread Starter
idles smoother at a lower rpm (cold start, no choke)
my 72 was just recently very lumpy on a cold start so i turned the idle speed screw in 1/4 turn. now it stalled! so i hooked up the oxygen sensor gauge, and opening the throttle caused it to go from 13:1 a/f to 15:1!
so i backed it out 1/8 turn and it is back to 13:1, necessary for a cold start with no choke or fast idle cam. warmed up it idles at 550 in drive.
It can be tricky to tune to run without a choke, so i thought i would pass along this info to those without an a/f gauge.
happy holidays!
so i backed it out 1/8 turn and it is back to 13:1, necessary for a cold start with no choke or fast idle cam. warmed up it idles at 550 in drive.
It can be tricky to tune to run without a choke, so i thought i would pass along this info to those without an a/f gauge.
happy holidays!
12-15-2001, 09:20 PM
#2
Safety Car
Member Since: Feb 1999
Location: Fountain Hills AZ
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Re: idles smoother at a lower rpm (drives61)
You make a good point and an excellent tip. If the trottle is open too far at idle it can result in using the main circuit instead of the idle circuit. The main circuit isn't designed to meter fuel very well at low velocities and an overly rich or lean mixture results. I suspect that a lot of carbs have been unnecessarilly replaced just for this reason.
[Modified by Vetterodder, 7:21 PM 12/15/2001]
[Modified by Vetterodder, 7:21 PM 12/15/2001]