Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: Jeffs68 on May 02, 2016, 01:39:43 PM

Title: Secondary air flaps
Post by: Jeffs68 on May 02, 2016, 01:39:43 PM

Is there any performance advantage to the secondary air flaps that have notches cut out of them as opposed to the ones that don't.

Title: Re: Secondary air flaps
Post by: carmantx on May 02, 2016, 05:24:48 PM

Depends on location of the POE, and engine/driving desire.  Some POE are under the valve and no need to slot.  Some are in line with the valve and again no need to slot.
In my experience, the secondaries can come in quicker and smoother with modified air valves.  Pontiac made the big slots in theirs.  They seem a little larger than needed.

Title: Re: Secondary air flaps
Post by: Jeffs68 on May 03, 2016, 06:13:06 AM

Thanks for the info :D

Title: Re: Secondary air flaps
Post by: Jeffs68 on July 01, 2016, 11:08:06 AM

Just an update/FYI, I had a very slight delay going WOT, and the trans dropped down with a nice jolt (2 speed), adjusted the  tension on the secondary air flap spring about 1/3 turn. It seem a bit too tight, but after the test drive, no delay and a nice smooth transition when the trans drops to LO.

Title: Re: Secondary air flaps
Post by: Jeffs68 on July 01, 2016, 03:43:48 PM

Just to clarify, I increased the tension on the spring by 1/3 turn.

Title: Re: Secondary air flaps
Post by: Cliff Ruggles on July 03, 2016, 04:03:27 AM

The secondary springs get weak and the plastic cams wear out.  I see a LOT of carbs in here with the springs wound too tight and ruined.  If you find yourself adjusting the spring past a full turn it's time for a new one.

Another big issue we've seen in recent years is the white plastic pull-offs currently being offered open too quickly.  We modify every one we sell to slow them down some. 

If the pull-off is too fast it requires too much spring tension to smooth transition.....Cliff