Thanks guys. As you say, it makes a difference. I understand how these small changes make a difference to flow as in a jet in the carb, but not so much in the needle and seat. I'm just amazed at the small change it takes from good to bad there.
By the way, my '52 GMC 228 3/4 ton flatbed came to me with a Carter YF 964S. Starts and runs great (avg. 14.7 MPG) except for when air temp is above 90F and shut off hot and allowed to set for 10-15 minutes. Wants to flood, but will start after 3-6 seconds of cranking.
'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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