Close

    • Why are B58 motors blowing? PureBoost.de/MHD Supra B58 teardown + blown B58 speculation

      It seems there is consistent string of blown B58 motors in the aftermarket. You may recall we first saw a blown tuned B58 with an F30 340i that switched to PTF's OTS Stage 2 tune back in 2019. Later in 2019 a PureBoost.de tuned MKV/A90 Supra B58 blew.


      MHD (who worked with Fabian at PureBoost.de) contacted BimmerBoost and stated their belief during their teardown it was a factory defect that caused the motor to let go. It's possible as BMW motors certainly have had their share of factory defects over the years.

      Here is what they said:

      Quote Originally Posted by MHD
      The tablet is broken thatís why they got a new one but the exact same map will be used to further develop the tune on the new engine

      It was 100% not the tune, the damage is pretty clear

      Tune would bent a rod, break a piston, etc

      But one single rod bearing is a manufacturing issue all others look brand new (engine had 2000mls)

      Car was running around 22 psi down low to 26-27 at red line, afr was around 12.2 and around 15 deg timing at red line

      Only a few small corrections up

      To 2 deg on 1-2 cylinders

      We still run full stock knock detection

      It was not a perfect tune but 100% safe
      Maybe it was the factory bearing?

      More:

      Quote Originally Posted by MHD
      Here is another picture you can see how the bottom bearing was not good, top one was fine

      All other cylinders were fine too





      Quote Originally Posted by MHD
      The complete block is good, no bent rods, broken pistons etc

      The guys did the first oil change after 1000mls and noticed quite a few metal bits flakes in the oil / filter but had no choice to investigate further and installed big turbo etc because they wanted to be the first and new fully built engine was on the way.

      The issue with the engine was one bad lower rod bearing
      They said the crank got damaged as well.

      So after this PureBoost.de rebuilt the engine and it's running strong.

      Now maybe this was a freak factory accident and bearing issue. BMW M motors are notorious for bearing issues over the years.

      How about this take on another blown B58?


      Many are reporting issues with cylinder six and excessive blow-by. Also, some state they believe CPI (charge pipe injection) has something to do with it and cars with upgraded HPFP's (High Pressure Fuel Pumps) don't see the same issues.

      What is the truth? Who knows. What we do know is as more motors let go and more are analyzed we get closer to figuring this out and making the B58 platform stronger and able to hold big torque.

      This article was originally published in forum thread: Why are B58 motors blowing? PureBoost.de Supra B58 teardown + blown B58 speculation started by Sticky View original post
      Comments 16 Comments
      1. Blown6's Avatar
        Blown6 -
        Maybe it just canít handle the stresses that come w/27psi
      1. 135idct's Avatar
        135idct -
        so the F series n55 is stronger
      1. AVI's Avatar
        AVI -
        Are the Supra B58 engines breaking too? This looks like a lubrication problem.
      1. nbrigdan's Avatar
        nbrigdan -
        Click here to enlarge Originally Posted by 135idct Click here to enlarge
        so the F series n55 is stronger
        Click here to enlarge
      1. F87Source's Avatar
        F87Source -
        Click here to enlarge Originally Posted by 135idct Click here to enlarge
        so the F series n55 is stronger
        Lol I highly doubt it but it is wishful thinking as an N55 owner.


        If it's blow by why is it only affecting cylinder 6? It makes sense if it was CPI related because there likely will be fuel distribution issues, and that is why imo CPI the most ghetto way to deliver fuel period. I also have zero clue as to why people still use these $#@!ty fuelling options when direct injection is now finally cracked. The higher flow variants should be able to support 700whp + on e50 so there isn't a concern for even more fuelling at this point. Plus there is a likely hood dual upgraded hpfps can be retrofitted soon like how it is done on the s55, to solve over 700 whp fuelling demands. When this happens PI would finally be considered an old outdated bandage imo.

        I'm just hoping the curse of the bmw ///M engine doesn't return (because this will likely translate to the S58), because so far there has always been issues with every single one of bmw's engine spanning from the E46 m3.
      1. Bowser330's Avatar
        Bowser330 -
        Why do bmw motors have these recurring bearing issues?
        The e46 m3 the e92 m3 and the e60 m5 all had bearing wear issues if I recall.

        Is it about the design? Are there bearing issues on other brand engines as well? Like evos, or gtrs, or 911s, or LS/T motors?

        is there a modification that’s not being done that could help prevent these issues?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by F87Source Click here to enlarge
        I also have zero clue as to why people still use these $#@!ty fuelling options when direct injection is now finally cracked.
        Cost?

        I'm waiting on upgrading my DI fuel system as well and I intend to do it with upgraded HPFP's.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        Why do bmw motors have these recurring bearing issues?
        The e46 m3 the e92 m3 and the e60 m5 all had bearing wear issues if I recall.

        Is it about the design? Are there bearing issues on other brand engines as well? Like evos, or gtrs, or 911s, or LS/T motors?
        With the S54 it was a bearing clearance issue that was resolved with a recall. The motor makes insane power even at 11.5:1 compression.

        With the S65 you also had a recall and you went to different oil.

        Who knows what happened. A bad supplier? A mistake by a drunk Bavarian? They eventually get it right.

        It's better to replace bearings to the proper tolerance than to figure out how to get a crank hub not to spin...
      1. F87Source's Avatar
        F87Source -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Cost?

        I'm waiting on upgrading my DI fuel system as well and I intend to do it with upgraded HPFP's.
        Dorch engineering and spool performance have made HPFP upgrades cheaper than the whole PI setup, no real excuses. If you're comparing to CPI that is the most ghetto thing ever, so if someone really wants to cheap out that much they should consider the cost of a new motor.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by F87Source Click here to enlarge
        Dorch engineering and spool performance have made HPFP upgrades cheaper than the whole PI setup, no real excuses.
        I agree completely.
      1. Roll up or pull up's Avatar
        Roll up or pull up -
        Typical trying to impress others and didnt wanna address the signs
      1. nbrigdan's Avatar
        nbrigdan -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        Is it about the design? Are there bearing issues on other brand engines as well? Like evos, or gtrs, or 911s, or LS/T motors?
        Subaru EJs are notorious for this.

        https://topclassactions.com/lawsuit-...on-settlement/
      1. onurleft's Avatar
        onurleft -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        With the S54 it was a bearing clearance issue that was resolved with a recall. The motor makes insane power even at 11.5:1 compression.

        With the S65 you also had a recall and you went to different oil.

        Who knows what happened. A bad supplier? A mistake by a drunk Bavarian? They eventually get it right.

        It's better to replace bearings to the proper tolerance than to figure out how to get a crank hub not to spin...
        It was never resolved on any car

        Complaints were answered. That's it. If you keep the motors hot, and drive them as intended they rarely have any issue. Race teams still change bearings frequently though. Later cars were given more tolerance for cold temperature, low RPM driving. They still consume bearings

        No motor that spins that fast, with a crankshaft that large will not have bearing consumption . Exotics of the past before these cars also consume bearings. It was an issue with the Murcielago as well as others when driven higher than usual miles. It's common for 458s to have shavings in the oil, they will also consume bearings, unlike other Ferarri's in the past due to there displacement
      1. Mm3boost's Avatar
        Mm3boost -
        Click here to enlarge Originally Posted by onurleft Click here to enlarge
        It was never resolved on any car

        Complaints were answered. That's it. If you keep the motors hot, and drive them as intended they rarely have any issue. Race teams still change bearings frequently though. Later cars were given more tolerance for cold temperature, low RPM driving. They still consume bearings

        No motor that spins that fast, with a crankshaft that large will not have bearing consumption . Exotics of the past before these cars also consume bearings. It was an issue with the Murcielago as well as others when driven higher than usual miles. It's common for 458s to have shavings in the oil, they will also consume bearings, unlike other Ferarri's in the past due to there displacement
        Good info. I always wondered what the limiting factor was, and it makes sense that it could be the length of the crankshaft vs the piston speeds.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by onurleft Click here to enlarge
        It was never resolved on any car

        Complaints were answered. That's it. If you keep the motors hot, and drive them as intended they rarely have any issue. Race teams still change bearings frequently though. Later cars were given more tolerance for cold temperature, low RPM driving. They still consume bearings
        They still consume bearings but I distinctly remember an S54 recall.

        On my S65 my bearings were replaced to a different tolerance. Not by BMW, by me.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by onurleft Click here to enlarge
        It's common for 458s to have shavings in the oil, they will also consume bearings, unlike other Ferarri's in the past due to there displacement
        Why would the 458 have issues and not other Ferraris when they are the same basic flat-plane crank V8 design?