Thermoquad question

we run a T.Q. on our 340 stocker. we use a oxy sensor in header collector to see a/f mixture. easy way to tune the carb. when we tried that, had a a/f mixture of 12.3 to 12.4 all way down the track, this was with a clutch car. that makes it a flat fuel curve. main thing done to carb, was get rid of the inlet piece. and tap carb for 3/8 pipe thread , adds volume of fuel to carb. i used brass nipple.