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I've seen it done on high HP cars before, but it was used as a tuning aid to help with boost ramps and the like.

Remember that boost pressure is really only a measure of restriction, and that compressing air generates heat. If you want 10psi, I would just pulley the blower to 10psi and tune it. By elevating impeller speeds, but bleeding off pressure, you really only serve to heat the air more - it doesn't get heated in the discharge tube, it heats when it's accelerated at the impeller. So basically you would still get the same amount of pressure - 10psi - but will a high likelyhood of elevated temps.
 

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Cyber Bully
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Procharger does not offer compressor maps for their superchargers. I made an excel lbs/per min calculator a while back to help me pick the right turbo. OP here is my best guess for your 3.7 mapped on a Vortech SI trim compressor map, closest comparison I have to a P1. (90% ve, 100* iat, 10lbs of boost with a wastegate, 7,000 max rpm).

Due to the engine size, you really don't generate a lot of air flow but rather a higher rate of pressure build up. By capping the boost with a wastegate you'll flow more air without increasing pressure, allowing the supercharger to move closer to its efficiency range.

The restrictor plate on a larger v8 like the vettes works okay since they flow a lot more air with little boost build up, and is already in the more efficient range on the compressor map, so you can sacrifice a little efficiency and still manage to get some extra power. You do it on your car and you'll just ride the surge line.




For comparison here is my car on a v2 map. Each green dot is 1,000rpms, boost is progressive to 8lbs. Notice that the increased displacement allows more lbs/min with less boost, better matching the efficiency range of the blower.

 
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