well I got lucky and used up my 50% off at Nue.......I used to order a 1512 1.5d to tun in my crt.5 on 3s and 4s....was going to get the 1509 2d but figured the 1512 would be more flexable to use in other bigger trucks......with 3s and 46 spur and a 14 pinion should run good