I understand and agree with your description above Jon, I just find it amazing that the difference in "push" on the needle through the two different seat sizes would be that critical.
Using 4 psi of pressure at the carb inlet, the .091 seat would apply 0.026 pounds (11.8 grams) of pressure against a closed needle while a .101 seat would apply 0.032 pounds (14.5 grams) of pressure. Not a lot of push.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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