The Powerdyne is the easiest to install, hands down. However, punching a hole in your pan is easier than you think. It's just a drain back line that's all, it's not high pressure. The powerdyne is very simple and I've changed the internal belt myself. It will break eventually but you can buy a belt for $60. It takes a few hours to pull it apart and put it back together. The Powerdyne is good if you want the sleeper attire. It's very quiet till you smash the throttle, then it whistles loud. The Vortech sounds like the world is coming to an end, it's great!!
All you here is straght cut gears churning baby! The Vortech is a more durable blower than the powerdyne. If you're going to do dragstrip launches you'll want the Vortech. The drastic drop in impeller Rpm's will snap the powerdyne belt after so many passes. But they're easy to change. If I were you, I'd buy the Vortech and punch your pan. You won't be disappointed, especially when you hear that thing whine. But powerdynes are great also. I love mine.
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92 GT, 4:10 gears, centerforce clutch, 6# powerdyne blower, bbk h-pipe, flowmasters