If I had to do it over again I would sell the engine and tranny and do a motor swap. Its not impossible to supercharge, just a lot of tinkering to get everything hidden from the ecu. Don't use a conventional water to air or air to air intercooler either. Meth/water injection is a must with 10:1 cr. Until someone figures out how to run a 2bar map sensor with the factory ecu its just not worth it. If I end up keeping my Xfire it is going to get a non MB V8 that has plenty of aftermarket parts/tuning abilities.