Street strip combos need a converter based on how much you want to favor the street or strip. Do you want it to approach lockup early for street? Or are you willing to tolerate a loose converter to go fast? The more stall you have up to about 85 % of your shift point rpm, the faster you will go. I made gains going to 6400/6600 flash with a 7100 shift point. I make within 5 hp of max at 6300 rpm. Obviously, you probably don't want to push it that far. But getting the motor up over peak torque into where the motor is close to peak hp is going to net you more hp to the tires ON AVERAGE , which yields best ET. So pick your own characteristics and have fun!