Q Jet Secoundary Rods

[SDT1DYI]

Having trouble getting the secoundary's jetted properly. Have several questions regarding rod sizing and tip lengths

Smaller the final tip size, does it always mean the richer the mixture? Do the tip lengths S, M, SM and L effect rich or lean condition with the same tip final size?
Why are LL tips never to be used in greater than 70% air valve opening?
Wanting to start on the rich side, is there good rod and hanger letter numbers to start with for a SBC 350 stocker for sea level conditions?

Tension on the Air valve. What effect does the tension have in 60ft times? Is it better to be on the loose side or on the tighter side using a 2 step WOT?.

Thanks to everyone for the help .

[Hacksaw]

The tip of the secondary rod sits in a fixed size orifice and acts as a restriction. So yes, the smaller the tip the richer the mixture. "They" say the long rods work better in drag racing but I have never seen any difference in testing. Don't know what LL tips are. Most guys measure tip diameter size for tuning, I go by factory stamps. An AU or CK rod is fairly rich. You really need a tool to properly measure the hangers. You can not go by the stamping. B or C hanger is on the very rich scale of things. The tension on the flap should not be to loose or a bog will surely appear. Don't think you will find much in the 60 with the flap once you have it set.

[Mike Pearson]

A good starting rod size is a .057 rod. Hot weather a .066 rod is what I use. J or K hanger is also a good starting spot. Beachy Machine makes the tool to check the hangers as I remember. Not sure if they still make them.

[nhramnl]

Mike Pearson is 100 percent on the money with his response. I bought a Beachy tool a few years back and Mike (Beachy) told me that at that time, they still had a few and would happily sell them.

[richie 2]

how do we get ahold of beachy tool?

[Mike Semeniuk]

LSM had a hanger checker - I'll post a picture later. Not sure if they still make it.

[SDT1DYI]

I made up a fixture to measure the hanger dimensions. Pretty easy to do. I had several Q jets so I sectioned one so I could see exactly how the secondary rod changes with hanger letter changes. K, G etc.
What I experienced on the Dyno, using LL .040 tips rods , thinking I was riching the secondaries, it went lean. Dont understand why??? I found the primary side jet size numbers can be way off, BEST to flow every jet you have to know for sure which way you are really going with your jet changes.

Thanks to all that responded.

[Hacksaw]

LL tip rods must be primary rods. I don't think anybody uses primary rods anymore in a race QJ.

[monte385]

The largest tipped rod I've used in my street machine has been .052. Usually in the mid .040's to end up 12..5 -13.2 afr.

[Jeff Stout]

Here is what I did to measure hangers. Some with the same hanger letter measured differently.Put hanger on end of caliper and use the same drill bit and measure distance and record. If you look close to this hanger it shows as being cut. That made it adjustable. Just bend at cut and remeasure. I believe this hanger came with my first Hedworth carb back in 1991.