HP is really dependent on a lot of factors. You should be able to count on 10 to 15 hp with that pulley. This is something that you will be able to feel with the butt dyno. Do you have, or do you have access to a pulley puller. It needs to be the correct puller made to pull supercharger pulleys. Anything else will destroy the old pulley.
To go any smaller with the pulley you will need to do things to your exhaust, PEMs, headers, rockers, CAM, stuff like that. Otherwise you will get boost stack and build up heat. You will also need to be able to scan the car for KR. Otherwise you risk damaging the engine.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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