Date: Thu, 15 Jan 1998 13:09:55 EST From: <BSTAFF51nopsame.edu> Subject: Filterchargers
I posted this on Saabnet.com but I thought I'd put it up here so everyone could take advantage of what I have learned. I have been told by a couple of auto-tuners that the K&N style filterchargers (the copper/gauze free flowing intake that eliminated the factory airbox) actually hurt performace of a car in everything except dyno-testing. When a filter like the one I have described is used in a real world situation it does not perform well at all. The idea behind these filters is to lessen the restriction of air going into the engine (more air= more power) But what is happening under the hood is that the engine is taking in high volumes of hot hot air. Hot air is less dense than cooler air, so in affect less air is getting into the engine. This air is not only less dense because it is hot is causes pinging, if you have a turbo this actuates the APC retarding the timing giving less power. I have a performance test from European Car Mag. on a VW VR6 that shows that the factory air box on that car would make more HP than one of those free flowing filtercharger systems. I post this beacuse of the few modifactions avalible to SAABers this is the most common one that can be and is done. Ben Stafford 85 900 turbo