Iff you are rideing with Standed cans on and Map 2 you will be runing way to rich for the cats in the standed cans Lamder sencers are swiched off on map 2 , so the C02 levels will be rong Lambder sencers whont be abule to talk to ECU'FI to lean mixcher off , so will run rich mid to top rev range cloging cats up and restrickting flow of gases leading to **** top end pirformence . Gen 2's on map 2 ,run rich'lean map botom end of the rev range ,it has to or it wood be unriderbule , so you whont notice eney thing till abowt 3000'rpm then it just runs a richer Map with no ajust ments from the lamder sencers .