Secondary air door types qjet

[Tyler73Deville]

Thought it'd be a good topic to start. Solid, Pontiac, modified solid, and the ones with the triangular cutout toward the back.

Which ones does everyone like and why?, what's the best one to use?

Much difference in how smooth the engine transitions to the secondaries between the flaps?

Also, Say the spring for the flaps is 1/2 a turn tight..do the little differences in the flaps affect when the engine start to pull them open?  I'd assume the larger opening would have them crack open just a tad later than solids given the same spring adjustment.

I personally use solids in both the Gto and Coupe DeVille but leave a little "slack" in the linkage to the dashpot. (Saw an old cliff post about doing that so I did) smooth transitions.

[Cliff Ruggles]

The best scenario is to use solid flaps with the POE exit holes under them, or at least in line with them so some of the opening is exposed below the lower edge of the flaps. 

For carbs with a high source location for the POE exit holes you can either "notch" the flaps to help that deal out and/or leave a small amount of slack in the linkage so the flaps "tip back" and allow POE fuel (or at least most of it) to go into the intake instead of out to and on top of the flaps.....