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mon-thurs 9-5 cst
The high side adjustment screw controls fuel to the high side nozzle or high side orifice. The high side adjustment is tuned for peak rpm of your engine. For racing, the needle is a tune on your longest straightaway or longest part of the course at wide-open throttle.
43-401 OE Tillotson High Speed Mixture Screw fits HL-129A, HL-166B, HL-166C,HL-189F, HL-274E, HL-324A, HL-352A, HL-382A