Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: 73ss on January 10, 2012, 05:01:44 PM

Title: Idle air
Post by: 73ss on January 10, 2012, 05:01:44 PM
I tore down this carb (7043200 '73 454), and was surprised to see how big the idle air was. Swallows a .125" drill bit so must be around .130. Idle tubes measured .038". I've never seen an idle air that big. Has anyone else? I usually see this around .030~.060. This carb appears to be un-molested. No drill marks. I bought the car that it came from 20 some years ago. Been sitting around since. Car was stone stock.

Tried to post a pic but can't get small enough. Went down on the pixels & still to big??
Title: Re: Idle air
Post by: Cliff Ruggles on January 15, 2012, 04:28:29 AM
Chevy big block application, and that is correct, they are larger than .125"....Cliff
Title: Re: Idle air
Post by: 73ss on January 17, 2012, 05:51:35 PM
Surprised to see a stock carb with idle air & idle tubes larger than what most of the recipies call for. 215 horse, lame cam, toilet bowl compression, 454. Wonder if it has large idle tubes to provide plenty of fuel once the limiter caps were broken off? I guess in most cases, this was done shortly after leaving the show room?
Title: Re: Idle air
Post by: Cliff Ruggles on January 19, 2012, 04:30:45 AM
Check the upper idle airbleeds closely.  Many will have pretty large idle airbleeds to go along with the larger idle tubes.....Cliff