Stay as far away as you can from BDS , Hampton, Weiand, Littlefield and a bunch of others are a lot better From personel experiences on three BDS street and strip blowers As far as the size I wouuld look at a 8:71 or even a 10:71, if it will fit, the bigger blower will make more pressure at a lower RPM, you won't have to spin the blower real fast to make boost in other words 7 lbs at 150 F at 3000 RPM is way better than 10 lbs at 190 F at 3000 RPM The faster you spin a roots type blower the more heat it will make, added heat makes detonation under boost There are coolers that can placed between the blower and the intake but most of them restrict the air flow and end up making less power at the same boost, a big interference in the middle IHTHs