I would also recommend a SC pulley but if you are set on the crank pulley, I would not go above 181mm. I ran 12.4 in a C32 with just a 181mm crank and OEM SC. Now I'm playing with a 164mm crank and a 62mm SC pulley and running into a lean condition. That's with a 550cc injectors. Stacked is not for a daily driver car unless you have some other means of getting to work.