Since I am no longer pursuing any kind of kit for the Crossfire I figured its about time to unleash what I know onto the forum so a few of you interested can experiment with the car. I shall not be liable for any catastrophic damage that may occur from the following procedures, do this at your own risk! Nothing in this thread pertains to the SRT versions

First of all force inducting the NA Crossfire is very much like force inducting any other naturally asperated vehicle with only a few exceptions.
We all know that the mechanicals of doing this are no major challenge so I am going to skip ahead to the basics of the tuning problems.
I'll call them Chucks 8 Commandments

1. Thou shalt hide boost from the ecu. This can simply be done by voltage clamping the MAP sensor to about 3.75volts. This may vary from car to car and current elevation. You can obtain an atmospheric reading from the map sensor with the ignition on and the engine not running with a voltmeter.
2. Thou shalt not produce boost at a throttle position lower than 15 degrees. If the Ecu calculates a large enough amount of air entering the engine via the MAF, MAP, and IAT at throttle positions lower than 15 degrees it will register a fault and cut fuel. So to make a long story short you must use a bypass valve. This also keeps the car from fuel trimming in closed loop mode(because of boost it can't read) at low throttles and cruising. This is the only solution to keep your Crossfire driving like it did from the factory.
3. Thou shalt regulate fuel under boost. You can do this with a rising rate fuel pressure regulator or your favorite MAP based extra injector controller. If using a rising rate fuel pressure regulator it is important to remove the factory regulator/filter and use a 3 bar fpr w/larger injectors. To put it simply, use a lower base pressure and larger injectors and the rising rate regulator. You may ask but Chuck whats the point in that? Well most RRFPR's are designed to work with 3 bar(43.5psi) base fuel pressure not our 58-60psi stock pressure. It won't raise the pressure until there is enough clamping force to overcome the base. Using an 8:1 rrfpr the pressure would not rise until almost 2 psi of boost are applied to it. Doesn't sound like a lot but lean is lean.
4. Thou shalt control timing. There are lots of companies that make piggybacks for this and until one of them sends me a fat check I'm not going to endorse the use of any of them. But we all know, at least us nerds that read all the forums, that Splitsec.com has a compatible programmable piggyback for this.
5. Thou shalt keep the MAF close to the throttle body. Unless you want to experience some real throttle lag, and not the imaginary kind the Sprint booster is supposed to fix(what a joke lol ).
6. Thou must use a MAF altering piggyback. This is for fine tuning the fuel trim in open loop. The ecu easily handled the closed loop fuel trims to stoichiometric.
7. Thou must monitor AFR. I used an Innovate LM1 wideband which also emulated the narrowband right out of the box. I got the best results around 12:1 AFR's.
8. Thou shalt use an intercooler. I used Methanol/water injection. With 10:1 compression ratio I think this is the most important part and will provide the most protection for your engine as well as power.

Hiding the boost was the most important part of this whole project because Mercedes being one of the smartest companies on the planet electronically safeguards their drivetrains in a variety of ways. This is meant to be a simple list of inexpensive ways to FI the crossfire and I'm sure there are a lot of other ways to tackle these problems. I still have lots of .5 inch waterjetted intake flanges if anyone wants to build their own intake manifolds PM me.