The WYL series of barrel venturi carbs are very good at running an engine on the lean side of the mixture. That works just great for those that need long durations, great fuel economy, or meet some mysterious EPA standards, but it doesn't work all that well for high performance applications. Most of any adjustments you will be able to perform will be on the low speed side of the circuit, not the high with but one or two model exceptions.

It could well be worth a little experimenting to see how changes to the inlet needle effect high end performance.