I dont know where this article got that idea from? the S54 is officially replaced with the S65, the N54 is replaced the M54 as a non-M engine. Untill we officially know what the new MZ4 will have, we can’t say anything about the Tubro engines replacing M engines.

Happy new year everyone, time to get ready to be drunk!

“BMW decided to retire the S54 and replace it with the twin-turbo N54. The engine will be remembered as the last high rev natural aspirated Inline-6.[3]”

http://en.wikipedia.org/wiki/BMW_M54#S54B32
referencing
http://www.motorauthority.com/bmw-retires-the-z4-ms-straight-six-engine.html

Thank you, that’s what I was trying to say but couldn’t spit it out. I knew that Valvetronic somewhat limited the engines in terms of performance but did return higher MPG.

A good example was the E90 320Si’s 4-cylinder developed for racing. The 4 banger didn’t come with Valvetronic like the standard 320i’s 4-cylinder thus the engine revved high but wasn’t nearly as efficient as it’s VVT brethren.

I think the reason for not having ValveTronic in M engines is the high RPM. The adjustable valves can’t Rev to 8k rpm.

Well, valvetronic is bmw’s VVT, right? I’d think that it would be useful for optimizing intake on any engine, esp naturally-aspirated ones (per Al’s recent engine posts).

Valvetronic also seems like it’s somewhat independent of other engine components, so they could easily remove it.

Does the N54 have valvetronic too? If not, it may be a candidate. I think M engines have problems when trying to run valvetronic.

Surely the next M3 won’t have a V8 and will be turbocharged. I had assumed they’d have a forced-induction version of the S54 (TT 3.2), and not reconfigure an existing engine like the N54.

I like the power of the S65. I like the fact that they kept it high-revving and lightweight. I hate the fact that the S54 has to be sacrificed, though. I think I just died a little bit.

I agreed that M should develop a ’smaller than a V8′ engine.. but for application in the 1 series. The Z4 has the space for it I’m sure, and lets not forget that the S65 V8 is 15kg lighter than the S54 I6!, for reasons of weight alone it might make sense to go for the V8! And lets not forget, the 507 that the Z4 is so similar in style too, was a V8.

Shame to see this engine go though.

The M-Powered V8 and V10 are great, but the I6 is the core of the M division and to be honest I hope the new MZ4 would come with a lighter and faster version of that great engine instead of the V8.