For some reason my original topic about this was deleted, along with my account for some reason. But anyway, found a powerflow air kit for a 90 535i at bavauto.com, and they are one of the top bmw tuner catalog companies. I have seen cold air for the e39, but never for the e34. It made such a huge difference on my e30, and it was going to be my first buy for my e34, but I couldn'yt find a kit ANYWHERE. I've heard that cone filters actually reduce hp for e34's, but I contacted bavauto, and they said I could try it for 30 days and get a refund if it isn't satisfactory. The kit is 100 bux, so should I get it? And to all other e34 owners- What did you do in the air filter category? It just looks so... Stock.