Head check: Let's talk about supercharger pulley ratios. Below is the chart we are discussing.

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The 65mm and 178mm pulleys are approximately a 15% increase in supercharger speed. Many have run these all day long with no fuel mods - easy power.

The 185mm and 62mm (61.9) pulleys increase the supercharger speed 20% and are great. An upgraded fuel pump and logging or tuning with a wideband O2 are highly recommended.

tighed1, Grip Grip, and jefasold have all had success in the 24% overdrive area with their 192, 181/71, and 181/70 combinations. Intercooling mods, major fuel mods, and a good tune are absolutely necessary to push the supercharger this hard.

I am the nutjob in the group overdriving the supercharger 32% with a 178/65 combo. I commuted in the car today and the torque is just crazy. I had a lot of fun. That is a big gap between me and those guys though. There are not any available combinations inside that range. I wonder if I might be able to back off the supercharger overdrive somewhat and still make as much power. We know that 66mm is the absolute minumim that a stock pulley can be turned down to. I have half a mind to have one machined down to 67mm or 68mm to test this.