In my opinion they are ok, but it may do a little better with a smaller carb´s. My friend has a stock cylinder, stock stroke Banshee. K&N filters, 34PJ´s, VF3´s, PD coolhead with 20cc domes, +4 timing and Toomey T5´s. No porting, but it runs good. 48 pilots, N8RE (KTM) needles, 152-160 mains.