Mark, sorry I forgot to mention the Venturi sizes it comes with. LMK if you want some inserts.

As with all engines, your tune will always be the perfect combination of all 3 needles. After break in and when any engine is ready for full out race tune, you should always start with the idle gap. Make the gap about the size of the end of a paper clip. I open a clip and insert it into the carb with no venturi. I then close my idle until it touches the clip. From there you tune the low end to make the idle drop to a purr as soon as you let off the throttle. The high speed needle will control the power and the fuel into the sway bar so you need to find that sweet spot between too rich and too lean. Make sure your engine and chassis are completely heat soaked before race tuning. Once I started tuning from idle my engines have performed much better and run times increased dramatically.