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mon-thurs 9-5 cst
The high side adjustment screw controls fuel to the high side nozzle or high side office. The high side adjustment is tuned for the peak rpm of your engine. For racing, the needle is tuned on your longest straightaway or longest part of the course at wide-open throttle.
43-987 OE Tillotson HR High-Speed Mixture Screw fits HR-181B, HR-184A, HR190A, HR-191C, HR-191G, HR-196A, HL-375A