hello lads and lady's. ive been trying to find some toothed pulleys for my g40 but it seems to be like finding a polar bear in Egypt. im just wondering what kind of difference does fitting a 63mm or 60mm pulley make? am i going to get more slipping and what kind of gains can be expected. im currently running a 65mm at 171hp. will it cause my engine much more strain?
it will over-rev the charger, the smaller the pulley the more RPM the charger itself is doing.
65mm is generally regarded as the smallest you can use reliably, smaller than that and you'll be blowing charger seals on a regular basis.