Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: Marx3 on March 28, 2010, 08:58:55 AM

Title: Idle-system
Post by: Marx3 on March 28, 2010, 08:58:55 AM

Hi, I was wondering; how far up through the rpm does the idle-system have effect on the mixture

Title: Re: Idle-system
Post by: Cliff Ruggles on March 29, 2010, 02:29:26 AM

It's more about throttle angle and engine vacuum than rpm.  The idle system is described in our book, and how each part of it works, etc......Cliff

Title: Re: Idle-system
Post by: Toronado on April 02, 2010, 03:16:37 AM

I heard idle sytem effects 0 through 60mph i do not
know if thats true, it sounded a little fast to me for the
idle system still effecting any thing much over 30mph.

Is there air and fuel still being feed from idle channels,
in tell a carb. reaches max rpm, mph, or vacuum (a ballpark number)?

Title: Re: Idle-system
Post by: Cliff Ruggles on April 02, 2010, 03:39:00 AM

As mentioned, it's about throttle angle, and engine vacuum created at the front edge of the throttle plates than will cause fuel to be pulled from the idle mixture screw holes and/or the tranfer slots.  This will not be the same for any two set-ups, but I would imagine most would be feeding some fuel to the engine thru the idle system at really low throttle angles and when the engine is pulling a lot of vacuum....Cliff