Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: pmathews on March 21, 2014, 11:18:34 PM

Title: 17056258 -> block the APT?
Post by: pmathews on March 21, 2014, 11:18:34 PM

I've enjoyed the book, but I am looking for more guidance on the 75-76 model with the non-desirable APT.  i've found a really clean 17056258, so I think it's worth saving, but I need some guidance on plugging the APT (or not).

I saw in an earlier post where you recommended to plug the 2nd power piston and jet, but you said to leave the APT operational?  Mine's a '76 and has the plastic spacer, not the aneroid, and it has an adjustment screw (+ rod and jet) in the large APT hole where the discontinued aneroid goes.  Is it worth keeping this and adjusting, or should I plug it, too?

Older thread -> http://cliffshighperformance.dreamhosters.com/simplemachinesforum/index.php?topic=1386.msg6421#msg6421

Thanks!

Title: Re: 17056258 -> block the APT?
Post by: pmathews on March 25, 2014, 08:13:53 PM

Here's a picture of the APT with the black plastic spacer (in place of the aneroid).  You can also see the metering rod.  There's a spring loaded screw on top that changes the pressure on the metering rod, thereby changing the depth of the metering rod in the APT metering jet.  From what I can tell, there's no vacuum that's applied to this setup, it's just a carry-over from when the aneroid changed the rod height.  I can't see how the black plastic spacer helps the situation.  That's why I'm wondering if I should just plug the APT jet.

(http://juaneita.com/cutlass/aneroid.jpg)