We can have custom size crank pulleys made. It would be about $250.00 and 3-4 weeks to have one made. The larger the crank pulley would mean the more the accessories would be overdriven. We have a 5.9 crank pulley on our vortech car. No problems with it. I would recommend to check fitment to make sure it will fit before ordering one. I would think a procharger or vortech would be fine.
Chris - Sales Dept.
407.339.9211 EXT 10
Please e-mail or call me for quicker response.