BMW M3’s 3.2-liter straight six engine comes to an end

BMW M3 | December 31st, 2008 by 19
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With sadness it is our duty to report that one of BMW’s best engine in the last 16 years has come to the end of …

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With sadness it is our duty to report that one of BMW’s best engine in the last 16 years has come to the end of its life. Codenamed S54B32, the 3.2 liter straight six cylinder engine “died” when the last E85 Z4 rolled out of the production lane this past summer. The S54B32 also powered one of the most popular M cars in the BMW’s history: the E46 M3. 

The S54B32 evolved from the S52B32 engine which powered the E36 M3 in the 90’s. It outputs 343 horsepower, 269 lb-ft of torque at 4,900 rpm. The engine was shared among the Z3 and Z4 M Roadsters and Coupe and it was one of the most admired engines by the BMW fans.

To quote the friends at Jalopnik, “The reasons for its popularity are two-fold: its specific power output exceeds 100 HP/liter without the aid of forced induction and its torque curve is fat, smooth and gap-free across the rev range. The S54B32 revs quickly, makes power everywhere, sounds like nothing else on the planet, responds instantly and, most importantly, is really, really fast.” 

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If you followed our article and analysis on the International Engine of the Year awards, you might have noticed that 3.2 liter straight six naturally aspirated engine won the award in 2001, the same year it was introduced as a new engine in the BMW line-up. For the next five years, it won the award for the Best Engine in the 3 liter to 4 liter category, an impressive run.

The new BMW Z4 will bring a new line-up of six straight engines, from the 2.5 liter 204 horsepower and 3.0 liter 258 horsepower to the 306 horsepower twin-turbo  3.0 liter engine. Many bimmer fans are nostalgic and are having a hard time adopting the new turbo engines in favor of the naturally aspirated ones, but according to BMW, this is the proper step in the right direction.

[Source: Jalopnik ]

S54B32 engine

19 responses to “BMW M3’s 3.2-liter straight six engine comes to an end”

  1. Auday says:

    The I6 is the first and the core of M-Sport division since the M88 of the M1. 6 independent throttle bodies, high oil pressure and high revving are all great characteristics of the I6 M engines from the M88 to the S54.

    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.

  2. Matski says:


    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.

  3. gunther says:

    I have now a Z4 M ,but I hope the new Z4 M 2010/2011 will be with
    the V8 .But I think is gone be something like tke 335i but upgrade

  4. Gragop says:

    Well this is a goddamn depressing thing to wake up to this morning.

  5. The Lee says:

    This is a sad, sad day. Out of every engine I’ve ever owned, from 400+ cubic inch American V8s to the little 1.6L inline 4 in my first-gen MR2, the S54 was my favorite. The only engine that came close was the 1L V-twin Rotax in my Aprilia.

    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.

  6. Volan says:

    A toast to one of the greatest engines to be remembered

  7. Doug says:

    Sad, very sad.

    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.

  8. Gragop says:


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

  9. Doug says:


    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.

  10. Auday says:

    The S65 is lighter because it’s newer, thats why I said they should have a “lighter and faster” version of the S54 that’s build with the same technology and materials of the S65 and revvs to the same RPM. I’m thinking something like S56 that is 30kg to 40kg lighter than the S54 and revvs to 8900rpm.
    The 507 is more like a luxury cruiser and is comparable to the Z8, the Z4 is an agile trackable car, so having an I6 in it makes more sense to me.
    Anyway, either engines are good as long as they stay away from the damn Turbos.

  11. Auday says:


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

  12. Gragop says:


    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.

  13. Doug says:

    Interesting… from wikipedia:

    “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]”

  14. Auday says:


    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!

  15. Horatiu B. says:

    @Doug: Wikipedia is not always right..but yes, there are many rumors that the turbo engines will power the M models.

  16. Damien says:


  17. Mike S. says:

    Good night, sweet prince. May you live on in the hearts of bimmerphiles everywhere.

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