Racing Fuel Systems

I've got an older 3 circuit 1050 annular booster dominator that I converted to a 2 circuit with qft metering blocks several years back. I run the ifr's in the low position and had tuned it with .040 ifr's and .056 t-slot restrictors with 75 air bleeds. 77 main jets 28 bleeds. Locked timing, 12-1 on sunoco 110 , iron heads. I hadn't run the car for a couple of years, and when I test drove it, the t slots were way rich. So I jetted down like 5 increments and ended up with .035 t-slot restrictors. Ran fine, but still rich in certain lower throttle positions. So I dropped the ifr's to .035 and tried .050 t-slot restrictors. Still rich, so I dropped the ifr's to .033 and it's pretty decent as far as seeing some upper 14's on the afr.
At first I thought the a/f gauge might have been off, but I recalibrated it, and it read the same. Then checked to p/v gasket, which is good. Metering block gasket is good as well. Anyone else ever have to run that small of ifr on a 1050 4500?

How big is the motor?

You are under a common misconception: that the IFR is sized for idle. It is NOT. The IFR supplies the T slot, with the T slot being the transition cct from idle to main cct. So the IFR is sized to provide the correct A/F ratio for transition.

I fully understand that the ifr's feed the transition slots. My question is if anyone else has ever experienced a situation where they had to use. 033 ifr's on a 1050 to get decent t-slot afr's.

I'd say .033 to .035 is about right. How many turns out are your idle mixture screws? Should be around 1 1/2, if lower than 1 I'd say you need less if over 2 I would say you need a little more.

1.5 turns out. The idle afr doesn't change between .040 and .035 ifr's, with the screws set the same. But did go up a tiny amount with .033 ifr's.

Perfect, any hesitation from idle?

No. It's got 50 cc pumps, and timing locked at 35, so it's got stupid throttle response everywhere. There aren't any drivability issues with any ifr I've tried , yet... it's more the issue of not wanting to soot up the plugs, waste fuel, and stink.

My thought is a fuel leak at the PV or PV plug gasket.