Your 540iA is plenty fast for the streets. If you have an extreme need for speed, then get a car for the track. Otherwise just make a trip out to the desert where no one (except you) will get hurt and hammer your machine out there as-is (we don't need no stinkin' superchargers!).
I was planning a supercharger for my 540i but have since decided to leave it alone and use it for what it does best, comfy easy going transportation. As for power, I have a 69 mach1 project that's getting C4 corvette front suspension, 4 link 9" rear end, and a 460 big block with aluminum heads, built bottom end, and two GTP38 80mm Powerstroke ford turbos. It'll be a street car weekend cruiser with 1200hp and the same for torque and should have no problem smoking up the tires going 100mph. But it won't have A/C, power leather heated seats, sunroof... Just raw performance. So... yup, keep your 540 naturally aspirated, add nice wheels and suspension if you wish, a nice stereo. But get a devoted racer or similar if you want something with flare. If you want to keep it relatively inexpensive get a car you can wrench on and without a lot of bells and whistles. Any time you seriously boost horsepower there will be maintenance involved. Then again, power with comfort is great but you'll be fighting an uphill battle with emissions.
cream an M5! Why else!? lol
<I>86 645CSi 5-speed</I>
<I>"Either you stand for something, or you fall for everything."</I>.
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