well i don't have a pes supercharger, but i spoke to one who does and u have to get a bunch of stuf like intercooler and exhaust but other wise, it give about 295 hp. so it's a good upgrade for about $4,995, if u have that kind of $ to spend. but i would get my car chipped first. if u have an info for a turbo on an 98 a4 2.8 quattro. please respond.