I'm possibly getting some awesome belt slippage with my Procharger P1SC that I'm trying to remedy. Using their 3.7" diameter pulley, I show ~7.5psi on my pillar gauge, but on the dyno recently they barely measured 3psi. I've noticed some black film/dust on the head unit and bracket, indicating some slip I'm assuming. The current belt tension seems tight and when pressing down perpendicularly, it has barely 1/4" flex. I don't recall if it was a Gates, or an off brand. I may try a Goodyear Gatorback next. In addition to that, I was reading on the Reichard Racing ultra-grip pullies. Twice the price as a standard pulley and I've heard they can eat a belt if not aligned properly, but I wanted to know if they have any reviews in here. Any other suggestions to look into are welcome as well. Thanks!

- How did the dyno measure your boost pressure? Where did they tie into? Same place your gauge pillar is measuring?
- Have you verified your belt alignment with a straight edge or anything like that?

Belt slip on throttle lift off is normal. If it doesn't slip you risk damaging the gears in the compressor.

Are you running the 8 rib setup? Possibly moving over to the 12 rib would get rid of the belt slippage.

Yes, they tied into the T where the boost gauge lines are. It's an electrical gauge btw. How is it the gauge would show 7+ and only measuring ~3 on the dyno?

I think the belt is aligned OK, but I do see a little white fray on one section, nothing major though. Mainly the black film makes me think it may be slipping at higher rpms. I am hoping a better belt and pulley helps, but not sure what else. I guess a boost leak is a possibility as well. How does 1 check for that, other than obvious connections in intercooling piping, etc.?

I'm using the 8-rib and it's not like I'm using a tiny pulley, I shouldn't have to swap to a 12-rib setup to see the correct psi.

Perhaps your electrical gauge isn't properly calibrated? If two gauges measured something different, I wouldn't assume leakage yet, i'd check for a bad gauge. See how you can calibrate the gauge.

How long have you been running that belt? If you've got some white fray and only have a few thousand km's on the belt i'd be concerned about it being out of alignment. I'm assuming the white fray is on a side and not the underside?

Less than a year on the belt and yes the small segment I noticed was on the side.