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    • Here's a single turbo N54 E92 335i with Schrick cams and a ported head revving to 8200 rpm

      The BMW N54 is not what you would call a high revving BMW engine or even a high revving BMW I6. There are numerous reasons for that such as it not being an M engine, being turbocharged, having direct fuel injection, an undersquare design, etc.


      More revs are very beneficial for those chasing more power especially when switching to a large turbo. Obviously with a larger turbo there will be a spool sacrifice but there will also be much more air moved up top. To really see the full capability a higher redline to take advantage of the torque curve that is now shifted to the right is needed.

      This E92 335i belongs to BimmerBoost member @jt0407 and here are a few of the specs:

      Supertech valvetrain
      Schrick cams
      ported head
      5 angle valve job
      Stock block

      Extending the redline over a 1000 rpm brings with it fueling issues especially on a direct injection system. He has a Fuel-It! Stage 3 setup with TBI:


      He claims he hit 8200 rpm there. Just for perspective still short of the stock 8400 rpm the S65 V8 revs to but a good step forward for big turbo N54's.

      As for the power he is making he says he will get on the dyno soon. It sure will be interesting to take a look at his power curve.

      This article was originally published in forum thread: Here's a single turbo N54 E92 335i with Schrick cams and a ported head revving to 8200 rpm started by Sticky View original post
      Comments 34 Comments
      1. jyamona@motiv's Avatar
        jyamona@motiv -
        8155rpm, to be exact Click here to enlarge
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by jyamona@motiv Click here to enlarge
        8155rpm, to be exact Click here to enlarge
        He said log showed 8200 so that's what I went by...
      1. TwistedTuning's Avatar
        TwistedTuning -
        DME Hard limit
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by TwistedTuning Click here to enlarge
        DME Hard limit
        The DME stops you at 8200?

        Another reason to get Syvecs but there is no way around this?
      1. TwistedTuning's Avatar
        TwistedTuning -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        The DME stops you at 8200?

        Another reason to get Syvecs but there is no way around this?
        yes, its capped by the storage type. a hair under 8200rpms. its probably capped for a reason beside that. HPFP would more than likely destroy itself spinning at that rate of speed or above that. Its the small things people forget about.

        So what if you can build engine to rev that high. if the pump grenades after a few passes, whats the point. the HPFP already has trouble with the engine spinning 7500rpms, lol. sure you can fuel it with PI. im moreso speaking on the internal damage that will eventually happen to the pump.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by TwistedTuning Click here to enlarge
        yes, its capped by the storage type. a hair under 8200rpms. its probably capped for a reason beside that. HPFP would more than likely destroy itself spinning at that rate of speed or above that. Its the small things people forget about.

        So what if you can build engine to rev that high. if the pump grenades after a few passes, whats the point. the HPFP already has trouble with the engine spinning 7500rpms, lol. sure you can fuel it with PI. im moreso speaking on the internal damage that will eventually happen to the pump.
        Makes sense.

        Can you not stop the pump if running PI and just solely use PI after a certain RPM?

        Honestly, if people are going to be revving super high the stock ECU just seems to become a huge headache.
      1. TwistedTuning's Avatar
        TwistedTuning -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Makes sense.

        Can you not stop the pump if running PI and just solely use PI after a certain RPM?

        Honestly, if people are going to be revving super high the stock ECU just seems to become a huge headache.

        HPFP is tied to the timing chain and etc. engine spins, so does the HPFP. also another thing to note on Direct injection. the higher you rev, the smaller the DI injection window becomes to inject fuel. Now you can offset this a bit by starting the injection earlier in the compression stroke, or even the intake stroke. But it will only open up but so much. Of course you could offset the loss of injection window of the DI with the PI, but then you start losing the ultimate benefits of DI itself. Its a balance.
      1. jyamona@motiv's Avatar
        jyamona@motiv -
        DME hard limit is 8160 rpm. It is limited by the use of 1byte storage for rpm in some places. 0xFF = 255 * 32 (scaling) = 8160.
      1. Aces's Avatar
        Aces -
        He will put it on the dyno soon? LOL
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Aces Click here to enlarge
        He will put it on the dyno soon? LOL
        Well so he claims...
      1. Terry@BMS's Avatar
        Terry@BMS -
        Serious RPM! In for dynos to see if it makes power up there.
      1. noorj's Avatar
        noorj -
        Click here to enlarge Originally Posted by TwistedTuning Click here to enlarge
        HPFP is tied to the timing chain and etc. engine spins, so does the HPFP. also another thing to note on Direct injection. the higher you rev, the smaller the DI injection window becomes to inject fuel. Now you can offset this a bit by starting the injection earlier in the compression stroke, or even the intake stroke. But it will only open up but so much. Of course you could offset the loss of injection window of the DI with the PI, but then you start losing the ultimate benefits of DI itself. Its a balance.
        Sorry but what are you talking about? No DI injection starts in the compression stroke (unless its cat heating, which still doesn't start there, just ends there), obviously 99% of the time SOI is in the intake stroke. To increase the injection window you can advance SOI slightly into the very beginning of the intake stroke if you stay away from gas exchange period, but you gain very little from that. The benefit comes from when you retard the EOI late into the compression stroke, that means later into the compression stroke.
      1. Flinchy's Avatar
        Flinchy -
        Click here to enlarge Originally Posted by TwistedTuning Click here to enlarge
        yes, its capped by the storage type. a hair under 8200rpms. its probably capped for a reason beside that. HPFP would more than likely destroy itself spinning at that rate of speed or above that. Its the small things people forget about.

        So what if you can build engine to rev that high. if the pump grenades after a few passes, whats the point. the HPFP already has trouble with the engine spinning 7500rpms, lol. sure you can fuel it with PI. im moreso speaking on the internal damage that will eventually happen to the pump.
        Doesn't the shotgun setup spin it 30% odd faster? Seems like they're fine spinning at the equivalent of 9500ish revs

        I don't see why many people would want/need over 8150, it seems like a pretty good number to me.
      1. Flinchy's Avatar
        Flinchy -
        Click here to enlarge Originally Posted by noorj Click here to enlarge
        Sorry but what are you talking about? No DI injection starts in the compression stroke (unless its cat heating, which still doesn't start there, just ends there), obviously 99% of the time SOI is in the intake stroke. To increase the injection window you can advance SOI slightly into the very beginning of the intake stroke if you stay away from gas exchange period, but you gain very little from that. The benefit comes from when you retard the EOI late into the compression stroke, that means later into the compression stroke.
        Stratified injection does
      1. noorj's Avatar
        noorj -
        Click here to enlarge Originally Posted by Flinchy Click here to enlarge
        Stratified injection does
        Yes, catalyst heating in the US or lean strat in europe. The main injection still happens in the intake stroke though, the secondary injection starts/ends late in the compression stroke. But again clearly we aren't talking about a region that would use lean strat here
      1. V8Bait's Avatar
        V8Bait -
        So about that window. Pictures to follow once correlated to crank and cam angles. It's currently static somewhere and chained to the crank.

        Nice RPM though, this isn't really new but it's the first ST I've seen it on. I've seen 2 6MT do this now but it always causes nice bog when shifting that high, how does the AT fare?
      1. dyezak's Avatar
        dyezak -
        Click here to enlarge Originally Posted by TwistedTuning Click here to enlarge
        yes, its capped by the storage type. a hair under 8200rpms. its probably capped for a reason beside that. HPFP would more than likely destroy itself spinning at that rate of speed or above that. Its the small things people forget about.

        So what if you can build engine to rev that high. if the pump grenades after a few passes, whats the point. the HPFP already has trouble with the engine spinning 7500rpms, lol. sure you can fuel it with PI. im moreso speaking on the internal damage that will eventually happen to the pump.
        You do realize that VTT has been overspinning HPFP's by 33% on their shotgun systems for a long time now right? So even with the stock 7000rpm redline that's effectively 9300rpm to the HPFP in the remote mount VTT supplies.
      1. Sticky's Avatar
        Sticky -
        So how long does the HPFP last then when overspun significantly?
      1. Itsbrokeagain's Avatar
        Itsbrokeagain -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        So how long does the HPFP last then when overspun significantly?
        I guess no one knows yet. Hasn't been run long enough in the field besides Tony's own car. We hope to have some feedback this fall.
      1. Sticky's Avatar
        Sticky -
        I guess I don't see how overspinning an already temperamental pump and lowering its life is a real solution. The higher you rev the more this is exacerbated.