Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: Rhett on May 09, 2012, 07:51:42 AM

Title: Secondary Throttle Plate Opening Angle
Post by: Rhett on May 09, 2012, 07:51:42 AM

Working on a 7041304, a service replacement for a 66 Buick Nailhead - My secondary throttle plates open past the angle where they would point directly at the bottom of the baffle. They dont open to 90 degrees, but it's not too far off - do I need to change that angle to point them back at the baffle? Is it hurting WOT performance the way it sits?

Thanks, Rhett

Title: Re: Secondary Throttle Plate Opening Angle
Post by: 429bbf on May 09, 2012, 08:14:32 PM

rhett i dont know if you have cliffs book. on page 80 he says to set the secondary throttle plates to exactly 90 degrees.thats the doctors orders for max. performance. dean

Title: Re: Secondary Throttle Plate Opening Angle
Post by: Cliff Ruggles on May 10, 2012, 04:46:49 AM

Unless you have access to a dyno or dragstrip, there is no way to really tell if being a bit before or after exactly 90 degrees is going to help.  All the dyno testing I've done here showed power loss if we deviated from a 90 degree open angle. 

There may be certain applications that favor otherwise, but none of the testing I've done here showed any benefits going over or under exactly 90 degrees....Cliff