I can speak from some experience and talking to many people Worldwide. I live in Germany and deal with an AC-schnitzer dealer In the Rheinland-Pfalz State of germany. The E-46 engine is pushing just about as much as it can. Herr Gleich says leave the computer alone and don't modify the air Intake. Modifying the these parts of the engine can put you in a high failure rate. Now, I have heard this from the top tuners of Germany. There is a high probability of mistake on your part when the limiters are gone. Not that you get to do max speed the M3 can do stock at home that is....LOL. I have upgraded my suspension with the Pro set and sway-bars offered from AC-schnitzer which I did not realize was Eibach. I am in heaven and would recommend it to anyone who wanted a better handling car. I had a 328i before and the M3 did not feel that much stiffer. Why use AC-schnitzer, because they offer the warranty that BMW gives on a new car and it is one of only 2 or 3 tuners to be able to sell in Dealerships here. I have the SMG II and want to put the 3:91 differential to the rear. I found out I might not be able to do this with the SMG II. However, I have contacted AC-Schnitzer germany and they have assured me that it can be done and it will take about a week to do the mod. This is where it gets interesting, the dealer has to remove my rear axle and have it specially fitted or matched to my rear axle. So if your boss has an SMG II he should definitely ask some questions if he will be trying to upgrade to the Next level. All that said, look to Dinan in the states, Steve seems to have the best handle on upgrading the M3 to the level to the CSL with Warranty. I don't have that option living here in Germany. Here is a Dealer in Dallas......
Autoscope
Address : 9796 Ferguson Road, Dallas, TX
Zip Code : 75228
Performance Representative : Nerces Mavelian
Phone : (214) 320-8280
Website : n/a
Let me know what your boss Does......DAVE
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