School me on supercharging a 360

StrokerScamp said
I don't have a ton of blower experience, but I have some. I've built three and helped with one that was a bracket racer. Blowers are expensive. As such, there's something that's never made sense to me. Almost everyone you see running one has it underdriven. This is stupid to me. I've always been of the mindset that if you're gonna spend 5K on one part, use the HOUND out of it. The one blown motor that I built for someone with a free hand was a 340 with a 6-71. We used costom JE pistons at a 6.5 to1 compression ratio and overdrove the blower 5%. He had to run on premium pump fuel, but that thing would really skin it back. This has been about twenty years or so ago. The more you use the blower, the more you can hear it. LOL Also, the volumetric effeciency goes through the roof. Blower motors are all about boost. The more you USE the boost, the better they run. I mean, it just makes no sense to bolt one on and underdrive it. To me, it's pointless.

You had to run premium on 6.5:1 compression? That must have been some serious boost it was pushing. Not that I can say I really know much about them, but the whole underdrive / overdrive thing has a lot to do with just how much blower you need. I've also heard underdriving is good because it helps keep the air temp down. I was debating this myself as I was waffling between a 6-71 and an 8-71 blower. I could get the same boost from the 8-71 underdriven (with possibly less heat generated from boost than an overdriven 6-71), but I would have to way overdrive the 6-71 if I wanted big boost for a race setup. The big thing is just to check out a blower chart for whatever you go with and figure out what kind of ratio you need. You can really make about whatever you want work if you mess with it. Hopefully I'll have that shiny blower on top of my car next year =P.