Author Topic: Secondary Throttle Plate Opening Angle  (Read 2103 times)

Offline Rhett

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Secondary Throttle Plate Opening Angle
« 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

Offline 429bbf

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Re: Secondary Throttle Plate Opening Angle
« Reply #1 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

Offline Cliff Ruggles

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Re: Secondary Throttle Plate Opening Angle
« Reply #2 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