[GmanJeff]

I've just ordered my 1st BMW (apart from a K1200RS motorcycle), a 2009 335I X-Drive, and have read with interest about the wide range and popularity of go-fast modifications for the 3-series cars. I'm particularly intrigued by mods like the SSTT,or the anticipated JB+, which seem relatively easy to install, and don't necessarily compromise the warranty if the tune is removed before having the car serviced. If I have understood the threads correctly, something like the SSTT can shave about 1/2 second from 0-60 times with no other mods to the car? What's the catch?

Do these types of mods mean that engine or transmission longevity or reliability is reduced? Do the cars become noiser, or less smooth in some way? If not, why wouldn't the factory make these enhancements either standard or as a factory option? Other than the cost of the devices, what is one giving up when installing these devices that increase boost?

[Panoz]

Transmission's and engine's longelivity could seriously affected/reduced even in a stock car depending on your driving behaviour. Marketing and research reasons(remember this is a newcomming BMW's philosophy engine and they want to test it...on our heads) kept more power away from this engine. But its beeing said that during testing period the first motors were performing safetly 370bhp.

As for the tunes i would propose you to get a tune that actually collaborates with your car's ECU and affects several parameters of the engine than a tune that actually tricking the ECU just to increase the "boost" parameter. A proper tune takes care of several factors and not just boost...and maybe fuel.