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    • Trouble in paradise? Vishnu/FFtec N54 335ii Single Turbo kits experiencing issues as a BimmerBoost member runs 12.5@121 with misfires and having to short shift

      BimmerBoost would like to thank member GeorgiaTech335Coupe for his openness and honesty regarding his Vishnu/FFTEC single turbo setup. Recently, this member took his single turbo upgraded 6-speed manual 335i to the PBIR (Palm Beach International Raceway) dragstrip in Florida to do some testing. His best run was a 12.50@121.6 alongside a 12.8@117. Yes, these times are quite a ways away from the 10.8@131 glory pass from Vishnu demonstrating the kits capability.


      This is in no way the fault of GeorgiaTech335Coupe who experienced misfires on his car and had to short shift at 6300 rpm in order to avoid them. Now, Vishnu has basically portrayed this kit as perfect and ready for sale with nobody having any issues. The reason BimmerBoost is bringing this issue to the attention of the community is for potential buyers to understand what they are getting into.


      There is absolutely nothing wrong with having issues when modifying a car to this level and BimmerBoost is confident Vishnu will resolve them. There is something wrong with pretending nothing is wrong. A few cars with the single turbo kits have gone up for sale and apparently a total of three people, that are willing to open their mouths, are having misfire issues with these kits.

      These issues will no doubt get resolved but potential buyers and current customers needs to be aware of the process, effort, and that progress is being made. Pretending nothing is wrong and collecting money simply is the wrong way to go about this and once again (it's becoming a trend) BimmerBoost is the only site bringing these issues to the attention of the community.

      For the record, a member by the name of @tmo335tt says he has a hardware solution for the misfires that he will likely share with Vishnu (hopefully not for free). Interesting that it isn't Vishnu but the community solving this.

      Thanks again to @GeorgiaTech335Coupe for sharing his details, good or bad, as we all learn thanks to honesty and openness. There is more to tuning than just collecting money.
      This article was originally published in forum thread: Vishnu Single Turbo at PBIR - 12.50@121.6 having to shift all gears at 6300rpm started by Sticky View original post
      Comments 1090 Comments
      1. TCW's Avatar
        TCW -
        So is there actual misfiring going on at 6300 rpm or is it a "false positive" misfire detection? So with the misfire detection disabled can the ST's with DMFW run just as fast as the SMFW ST's?
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Click here to enlarge Originally Posted by TCW Click here to enlarge
        So is there actual misfiring going on at 6300 rpm or is it a "false positive" misfire detection? So with the misfire detection disabled can the ST's with DMFW run just as fast as the SMFW ST's?
        Why not put a DMFW on a SMFW car and get it to misfire in the name of science (or in this case, business)? Shiv could've (or should've) done this easily instead of having his customers go out buying flywheels
      1. themyst's Avatar
        themyst -
        Click here to enlarge Originally Posted by Terry@BMS Click here to enlarge
        They can't flash at home. He would have to mail the DME in for that...
        I keep assuming everyone runs cobb as the base. Forgot all about the Vishnu flash. Honest mistake.
      1. GeorgiaTech335Coupe's Avatar
        GeorgiaTech335Coupe -
        Click here to enlarge Originally Posted by themyst Click here to enlarge
        Just disable misfire detection and go back to the damn track! Click here to enlarge one run and u can flash back after to whatever you want.
        I will if the SMFW doesn't fix it. Otherwise, like Terry said, I'll have to mail my DME in. The clutch/SMFW will get here before then so we will just have to wait.

        Trust me, I'm way more anxious than anyone here...that clutch is getting broken in within a day or 2. I'll drive all day if I have to.
      1. Terry@BMS's Avatar
        Terry@BMS -
        Click here to enlarge Originally Posted by TCW Click here to enlarge
        So is there actual misfiring going on at 6300 rpm or is it a "false positive" misfire detection? So with the misfire detection disabled can the ST's with DMFW run just as fast as the SMFW ST's?
        Excellent question. Despite the literature saying it would be a false misfire detection Shiv indicated he thinks it's an actual misfire:

        Click here to enlarge Originally Posted by Shiv Click here to enlarge
        In the case of high HP 6MT cars with stock DMFW, disabling misfire detection isn't the problem itself. The more likely problem is ignition timing/spark advance jitter caused by an erratic CPS waveform. The scope readings showed the falling edge of the crank sensor signal to move around quite a bit when the flywheel induced error occurs (high RPM, high boost).
        It's not clear how he is determining the crank sensor signal is moving around as a result of a "flywheel error", and not an actual misfire. It's very difficult to differentiate between the two IMHO. And any sensor noise would be picked up as a gap error. But at this point these guys have flywheels on the way so let's all just hope that fixes their problems.

        Someone posted this video on e90post which I found useful in understanding exactly how the DMFW operates:

      1. redlineryder's Avatar
        redlineryder -
        Click here to enlarge Originally Posted by dzenno@ProTUNING Freaks Click here to enlarge
        Why not put a DMFW on a SMFW car and get it to misfire in the name of science (or in this case, business)? Shiv could've (or should've) done this easily instead of having his customers go out buying flywheels
        Good point.
      1. Sered's Avatar
        Sered -
        Click here to enlarge Originally Posted by dzenno@ProTUNING Freaks Click here to enlarge
        Magnetic pickup? CPS is hall effect not magnetic which is part of the reason why vibrations there don't matter as much as with a magnet based CPS

        Did you have something else other than CPS in mind when you said magnetic pickup?
        Correct me if I'm wrong, but Hall effect IS magnetic. It's a magnet (generally a rare earth magnet) with a ferrous object passing through its magnetic field, inducing a current.
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Click here to enlarge Originally Posted by Sered Click here to enlarge
        Correct me if I'm wrong, but Hall effect IS magnetic. It's a magnet (generally a rare earth magnet) with a ferrous object passing through its magnetic field, inducing a current.
        There is no magnetic "material" in a hall effect sensor. It uses an electric current to create a magnetic field (a la electro magnet). Wikipedia is a good source of info. Here's also an article more related to CPS

        http://www.enginebuildermag.com/Arti...n_sensors.aspx

        I guess by pickup he meant magnetic "field"
      1. rudypoochris's Avatar
        rudypoochris -
        Click here to enlarge Originally Posted by Terry@BMS Click here to enlarge
        Excellent question. Despite the literature saying it would be a false misfire detection Shiv indicated he thinks it's an actual misfire:



        It's not clear how he is determining the crank sensor signal is moving around as a result of a "flywheel error", and not an actual misfire. It's very difficult to differentiate between the two IMHO. And any sensor noise would be picked up as a gap error. But at this point these guys have flywheels on the way so let's all just hope that fixes their problems.

        Someone posted this video on e90post which I found useful in understanding exactly how the DMFW operates:

        http://www.youtube.com/watch?feature...;v=DbvP5EvpUbA
        Good video. The misfire may be recorded when the "bump stops" of the second stage contact at high frequency. That connection would probably be pretty rough. Just speculating.
      1. Sigma 3's Avatar
        Sigma 3 -
        Click here to enlarge Originally Posted by Q4P Click here to enlarge
        Very nice of you to notice... I havent been on the post for over a year now.
        Why would you lie about this ? You where on there less than a month ago?
      1. Q4P's Avatar
        Q4P -
        Click here to enlarge Originally Posted by Sigma 3 Click here to enlarge
        Why would you lie about this ? You where on there less than a month ago?
        Sure... you are very free to point out the 10-15 posts that I have made in the last 6 months in the tech section. I guess you misunderstood when I meant; which was actively participated.

        Curious when the Supra comment was made...
      1. JStang's Avatar
        JStang -
        Any updates? Someone has to have gotten their SMFW by now right?
      1. rudypoochris's Avatar
        rudypoochris -
        Click here to enlarge Originally Posted by JStang Click here to enlarge
        Any updates? Someone has to have gotten their SMFW by now right?
        They have to give time for Shiv to finish modifying the logs and give the thumbs up before posting.Click here to enlarge
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by rudypoochris Click here to enlarge
        They have to give time for Shiv to finish modifying the logs and give the thumbs up before posting.Click here to enlarge
        close, they are waiting for their ECU's to get mailed back with misfire detection off, to claim the fw was the culprit..
      1. jpsimon's Avatar
        jpsimon -
        No matter what the outcome is you guys will find something ridiculous to complain about, even if it is as simple as the flywheel needing replacement.
      1. GeorgiaTech335Coupe's Avatar
        GeorgiaTech335Coupe -
        New flywheel and clutch is getting installed tomorrow afternoon. I'm going to try to put 300 miles on it after the install. Then we will know the results.
      1. LostMarine's Avatar
        LostMarine -
        i see said the blind man..
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Click here to enlarge Originally Posted by GeorgiaTech335Coupe Click here to enlarge
        New flywheel and clutch is getting installed tomorrow afternoon. I'm going to try to put 300 miles on it after the install. Then we will know the results.
        Good luck man, really hope it'll work out, otherwise you know what to do Click here to enlarge turn it off
      1. lulz_m3's Avatar
        lulz_m3 -
        Click here to enlarge Originally Posted by GeorgiaTech335Coupe Click here to enlarge
        New flywheel and clutch is getting installed tomorrow afternoon. I'm going to try to put 300 miles on it after the install. Then we will know the results.
        Good luck buddy, are you planning to hit the strip anytime soon? I might have to make the trip down south to see your beast run and see what i can squeek out.
      1. jpsimon's Avatar
        jpsimon -
        Click here to enlarge Originally Posted by GeorgiaTech335Coupe Click here to enlarge
        New flywheel and clutch is getting installed tomorrow afternoon. I'm going to try to put 300 miles on it after the install. Then we will know the results.
        nice!