Fast Idle question..

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Mar 28, 2005 | 10:47 AM

Rhufus

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From: Western PA

Fast Idle question..

My '78 L-48 fast idles @ 1500 RPM. I really don't need it to idle that fast. How can I slow it down without "screwin" something else up?

Thanx

Mar 28, 2005 | 11:07 AM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

Back off the fast idle screw and set it where you want it. That won't affect anything else.

Mar 28, 2005 | 11:11 AM

74FLCONV

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From: Manalapan FL

If my car hasn't been run for awhile, the "kick-down" for the fast idle doesn't release. I have to stick my fingers in the linkage and manually release it. This linkage is on the passenger side of the carb, buried behind the choke.

This may be your problem. What carb are you running? Mine is the Edlebrock replacement for the Q-Jet. I had the same problem with the original Q-Jet.

D. Ocean
Miami, FLA

Mar 28, 2005 | 02:08 PM

rihwoods

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Quote:

Originally Posted by Rhufus

My '78 L-48 fast idles @ 1500 RPM. I really don't need it to idle that fast. How can I slow it down without "screwin" something else up?

Thanx

No comprende ? Do you "kick it down" after warm up ? Need clariifcation.

Mar 28, 2005 | 02:34 PM

Rhufus

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From: Western PA

I'm running the original Q-Jet. It does kick down after warm up. The problem is pipes and the "be a good neighbor thing".

Just don't need it idling @ 1500 RPM's.

Mar 28, 2005 | 09:04 PM

rihwoods

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Quote:

Originally Posted by Rhufus

I'm running the original Q-Jet. It does kick down after warm up. The problem is pipes and the "be a good neighbor thing".

Just don't need it idling @ 1500 RPM's.

That may be a reason to adjust your "fast idle".We are only talking five minutes of warm up.In Calif they allow 95 decibels for performance exhaust.What they allow in your state ? Mine "fast idles" at 1500 rpm at probably 85 decibels or so.No big deal.

Last edited by rihwoods; Mar 29, 2005 at 09:46 AM.

Mar 28, 2005 | 10:49 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

Quote:

Originally Posted by Rhufus

Just don't need it idling @ 1500 RPM's.

Just back off the fast idle screw about a half turn and get your idle speed down around 1000 -1200. It takes 4 seconds to give the screw a twist once you can see it. I agree 1500 is a bit fast - you don't need it that high, and that's a lot higher than spec. I set up most of the carbs I do to about 1000-1100 on the fast idle.

Mar 29, 2005 | 03:26 AM

Turbo-Jet

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From: Vancouver BC, Canada

Does the throttle pedal follow the fast idle setting? ie: if on the high step the throttle blades will be held open off the regular stop and the pedal will not spring back as far?

Sounds right, but I've never actually noticed this before.