[zenmaster]

Stressdoc is following the subject. From http://www.e90post.com/forums/showth...=50621&page=10 :

I am not an engineer at BMW AG but I do have contacts wth the engineers that work at FIZ. I want to share some information that may be useful, and I apologize in advance if you guys already know most of this. All numbers quoted are DIN at the crank.

BMW is working at releasing an N54 HP motor by the end of this year. Although the platforms that will be equipped with this version have not yet been decided, it is safe to say that the E90 through E93 platforms will get it as soon as it is available. The expected HP rating is around 355PS, up from the standard 306PS of today's motor. The current HP test engines have exacerbated a problem that already exists on the current 306PS motor, where the temperatures of cylinders 5 and 6 are higher than expected and are a huge cause for concern. BMW is looking at a solution to this problem, and is also anticipating that they may experience some engine failures on the current motor. What is clear, is that they heve to wrestle the cause of the problem, and/or find a solution, before they release the N54 HP version into the market.

In typical BMW fashion, these issues are monitored without being made public, as they do not want to have to answer to any unwanted warranty claim, or even worse, be forced to issue a general recall that may prove to be unecessary, as they will address the isolated cases on a one-by-one basis. This is no different than how they handled the piston ring/oil consumption problem on the early S62 motor. Don't be surprised, if they should decide to keep the standard 306PS version alongside the HP (i.e. in the 135i), to see next year's engine to be a little different than what is offered today.

If any of you have driven your 335i hard, you may have noticed a tendency for the oil temperatures to be a little high. The problem is that the temperature gauge is measuring the average temperature once the oil recirculates, so you can imagine, if cylinders 5 and 6 are the ones generating most of the heat, that this is an area that could be prone to failure.

Recently Alpina introduced their Alpina B3 BiTurbo at the Geneva Auto Salón. The car is rated at 360PS, and this is the level of power that BMW feels safe with at this point. We may sit here and go back and forth on who of the vendors on this board produces the most power and why, but surely nobody will try to argue that Alpina does not have the resources, nor the expertise, to extract every bit of power from the N54 motor. Just keep in mind that they have had experience with turbocharged BMW motors that goes back 30 years, and have been consulting with BMW on the development of the N54 motor itself.

Like Alpina and BMW, Racing Dynamics S.p.A. and its U.S. arm RDSport are approacing this subject with caution, and our current offering is a result of many factors: the main one is the oveheating issue, but most of the others haven't even been mentioned anywhere in this thread.

Good luck to all.

Racing Dynamics S.p.A./RDSport
Federico L. Pavoncelli
President

Presumably, the same changes that BMW will need to make to their 355 HP N54 HP engine would be the same to which Dinan is referring.