Last week I was the 4 cycle tech inspector at the Arizona Karting Assoc.'s Holiday Classic. Great racing on a great track. This year they invited the LO206 Sr. class from the neighboring sprint track to compete in their own class using the sprint track rules and TIRES (4.6 front, 6.0 rear, Envico blue ( mid 60's duro, no prep). Only changes made to the karts ( CIK bodywork ) was narrowing the rear width.
Surprisingly they were only .1 sec. off the lap times of fully prepared speedway karts with BP clones. ( IKF Super Stock rules)
I'm told by a local engine builder that his dyno shows the clones with a HP advantage. Just something to think about!