• BMW 2.0 liter four cylinder N20 turbo motor already having issues? Head cracks under stress above 331 pound-feet of torque?

      Some interesting information was posted in the N20 section of the BimmerBoost BMW forums regarding the durability of the N20 motor. Now, the motor is becoming very popular and is winning multiple awards and rightfully so as it is currently the best factory 2.0 liter turbo four cylinder in production. The keyword there being factory as apparently it is not going to be a stout aftermarket tuning platform at least not yet. Take the information you are about to read as unconfirmed but from an interesting source.

      There are companies that stress test engines for OEM's. One of these companies has been testing the N20 apparently. The advice given is not to go beyond Stage 2 on the N20 which means a slightly more aggressive tune on the factory turbocharger. Why? The N20 head apparently cracks at around 331 pound-feet of torque. That is not exactly a whole lot of torque in the turbo tuning game especially considering the motor puts out an underrated 258 pound-feet from the factory.

      Apparently the engine is just running very hot and multiple heat cycles are creating problems. BMW behind the scenes is supposedly trying to correct the issue. For whatever reason BMW seems to have a reputation for problems with new motors. S54 bearings, S65 bearings, and the next BMW new motor issue looks to be the N20 head cracking.

      The story is that one of the lead designers and engineers for the N20 was flown out to the USA to inspect the findings for himself. It is doubtful BMW would do that unless there was something of substance to this. This same company also apparently tested other BMW motors including turbo motors such as the N54 and N55 when they were new and they did not run into these head issues.

      So what is going to happen? Well, right now it is not recommended for N20 owners to push their motors too far which they can't anyway as there are not aftermarket turbo options out just yet. BMW will likely resolve the problem with a new head which will mean for those with the N20 there will either be a recall or there will be a BMW part number option to get the new head. We will have to wait and see what happens but N20 owners should be aware of the potential issue especially if intending to tune as BMW is unlikely to say anything until they have to.

      This article was originally published in forum thread: N20 Owners started by VargasTurboTech View original post
      Comments 145 Comments
      1. George Smooth's Avatar
        George Smooth -
        I hope they keep the new 6 simple in the New M so we can see upgrades far sooner.
      1. DFM's Avatar
        DFM -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        I hope they keep the new 6 simple in the New M so we can see upgrades far sooner.
        That is a pipe dream my friend
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by bobS Click here to enlarge
        Why? What's wrong with the n54?
        A lot.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by VargasTurboTech Click here to enlarge
        In my personal opinion an I6 is the engine that belongs in the M3 its the motor I think of when I think M3.
        And everyone skips over the E30 M3 for some reason as if it doesn't exist with its four cylinder?
      1. VargasTurboTech's Avatar
        VargasTurboTech -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        And everyone skips over the E30 M3 for some reason as if it doesn't exist with its four cylinder?
        no idea why you have such a hard on for the N54 and how bad it is. I could not disagree more. And who skipped over anything? I said in my mind when I think of M3's I think inline 6. Obviously in your mind you do not. That's fine, the N54 is an awesome motor and I would choose to be working on that platform over the S65 everyday and twice in Sundays. Again my opinion
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by VargasTurboTech Click here to enlarge
        no idea why you have such a hard on for the N54 and how bad it is. I could not disagree more. And who skipped over anything? I said in my mind when I think of M3's I think inline 6. Obviously in your mind you do not. That's fine, the N54 is an awesome motor and I would choose to be working on that platform over the S65 everyday and twice in Sundays. Again my opinion
        I don't call the N54 bad. I'm not putting it down. I don't think the M3 has to be a six cylinder by any means.

        You are more than entitled to your opinion.
      1. bobS's Avatar
        bobS -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        A lot.
        I dunno, I think the guy in the e46 m3 I just smoked on the way to the beach is thinking there is something wrong with his carClick here to enlarge

        It was a great way to start out the weekend, he was revving at me at the light, and he got crushed, gf laughing at him, lol ....poor stock e46 m3.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by bobS Click here to enlarge
        I dunno, I think the guy in the e46 m3 I just smoked on the way to the beach is thinking there is something wrong with his carClick here to enlarge

        It was a great way to start out the weekend, he was revving at me at the light, and he got crushed, gf laughing at him, lol ....poor stock e46 m3.
        Nothing better than crushing someone who asks for it.
      1. bobS's Avatar
        bobS -
        Yup, I love the e46 m3 too....

        Btw I drove my wife's x3 with the n20, it has a automatic engine shutoff when you come to a stop, kinda strange but I guess it saves fuel. Also, rather than a mpg gauge there is a electric gauge that has "efficient dynamics" written in blue and it glows when your driving calmly/fuel efficient kinda dumb.... But the n20 is awesome, very stout for a 4 cylinder...
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by bobS Click here to enlarge
        rather than a mpg gauge there is a electric gauge that has "efficient dynamics" written in blue and it glows when your driving calmly/fuel efficient kinda dumb
        Gimmick.
      1. bobS's Avatar
        bobS -
        Yup.... The ford escapes I buy for our sales reps have green leaves that appear when you drive efficient lol...so dumb
      1. rader1's Avatar
        rader1 -
        Wait, they tested N54s and N55s at 650hp when they first introduced?
      1. ajm8127's Avatar
        ajm8127 -
        Its really common to test a design to its breaking point. When you are dealing with something as complicated as an engine, it makes sense to contract that work out to a dedicated testing firm.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by rader1 Click here to enlarge
        Wait, they tested N54s and N55s at 650hp when they first introduced?
        Apparently.
      1. rader1's Avatar
        rader1 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Apparently.
        I wonder how they did that when there wasn't(and still isn't for the N55) 650hp worth of turbos available?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by rader1 Click here to enlarge
        I wonder how they did that when there wasn't(and still isn't for the N55) 650hp worth of turbos available?
        You don't understand the difference between bench testing and in car testing?
      1. VargasTurboTech's Avatar
        VargasTurboTech -
        Click here to enlarge Originally Posted by rader1 Click here to enlarge
        Wait, they tested N54s and N55s at 650hp when they first introduced?
        Yes, A friend of a friend of a friend of a guy who is on the forums is an engine tester for BMW and that guy posted unsubstantiated claims on the forums that actually don't add up and for done reason people are buying in. Lets get this back on track, this is a thread for the FOUR CYLINDER N20 and turbo upgrades for it. Lets try not to turn this into another S65 vs N54 thread or N54 thread. Cheers guys
      1. Zero's Avatar
        Zero -
        Just wanted to bring this back to the n20 for sec. Really happy to see a potential turbo upgrade. Even if it is more on improving the turbos efficiency than making lots of power. I love my n20, but I was realistic when I bought it. Knowing it would be fun, but if I wanted to have screaming turbos I should get the n54/55.

        i currently have the stage2 from terry, and dp's....can't wait for a charge pipe, intercooler and your turbo upgrade. That should hold me over till I get something new in a few years, and be plenty of power for for my n20.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Zero Click here to enlarge
        but if I wanted to have screaming turbos I should get the n54/55.
        The N55 doesn't exactly have a "screaming" turbo. It's fairly limited too. Much more will come in time.
      1. Zero's Avatar
        Zero -
        I meant it in the sense that if I wanted a car to mod the living day lights out of, and spin tires I would have gotten the six cyl. But I wanted to be on the more economical side of things, so I got the 4cyl.

        dont get me wrong, I'm sure th n20 will rock. But if I was looking to make big hp I would be kidding my self by not getting the larger motor.