• First high torque N54 (335i/135i) steptronic transmission build completed by Level 10 Transmisisons - ~700 pound-feet capable

      As many of you know, BimmerBoost user LostMarine got his 335i Steptronic transmission built by Level 10 to handle increased torque as his upgraded turbos took their toll on the stock transmission. Turn around time was surprisingly quick and should be 10 days and under for all N54 transmission builds. LostMarine had the transmission built along with upgrading the torque converter with a higher stall and the valve body. Price will vary depending on options.

      In Lost Marine's words:

      So here are the details I can speak of. Car runs strong, very solid and strong now. Much improved over what I can remember even when I first bought the car. Here she is as the short journey began. Luckily the car was only down for about 1-1/2 weeks










      Clutches were fried in mine as you can see from this pic.


      They were replaced with stronger material obviously. Now rated up to 700ft/lbs




      Tq convertor was setup for mild street use and increased stall RPM by 500.


      Sorry no more pics on that

      VB Pressure was increased from the stock 60-70psi to 130 psi.

      Pump volume was also increased in total flow from 2qt's/30 seconds to 3 qt's/30 second

      All of this translates in the much stronger and firmer shifting that I have been noticing.

      I have to say, for being a BMW and asking for a mild street use Transmission , Level 10 Delivers.

      The higher stall has nearly no affect on the DD driving characteristics of the car. I do not feel any "slack", and had i not known the stall was increased, I could never tell.

      I had planned on attaching video of the car/trans going through the gears, but the angle was way off. I attempted to have it catch the sound and speedo/Tach so you could see the correlation, along with Datalogs. The roads today were not easily manuevered though.
      This article was originally published in forum thread: First high torque N54 (335i/135i) steptronic transmission build completed by Level 10 Transmisisons - ~700 pound-feet capable started by Sticky View original post
      Comments 64 Comments
      1. Itsbrokeagain's Avatar
        Itsbrokeagain -
        hmmm. I should get on this and see if I can get some people to send in their trans Click here to enlarge. Something else for me to sell to my customers Click here to enlarge
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Eleventeen Click here to enlarge
        I've heard that a properly matched upgraded torque converter can be good for nearly a half second reduction in 1/4 mile times. If they properly matched the converter to his powerband, he should be able to leave the line under very high boost.
        I wouldn't expect half a second but the higher stall will help him.
      1. PEI330Ci's Avatar
        PEI330Ci -
        Very nice!

        Has the cooling issue been addressed?
      1. LostMarine's Avatar
        LostMarine -
        I havent done anything to add to cooling. Ive got about 300 miles on it right now.. Im gonna go back up there soon for software changes and ill see about adding an external cooler
      1. Itsbrokeagain's Avatar
        Itsbrokeagain -
        lets make one Click here to enlarge Im sure Andrew could supply us a few things and we could make one up ourselves..
      1. LostMarine's Avatar
        LostMarine -
        OK, so here are some video's for you guys for comparison.

        JB4-- Default map 7- 93 octane, DO14 (60/40 Meth)

        Here are going through the gears normal DD driving in "D'








        Going through the gears normal DD driving in "M"





        and a WOT run (with log) in "D"

        (i didnt even go WOT until 3rd really as you can see from the log)



        Click here to enlarge


        and WOT run in "M"

        (I forgot to shift a bit before redline though)



        Click here to enlarge



        Barely 15- maybe 16 PSI on the first run. Im still taking it kinda easy on the trans. next up is my old favorite, the custom Map 6 with 17-17.5 PSI
      1. enrita's Avatar
        enrita -
        Great videos, thanks for taking the time !
        Seems more consistant and locks firmer by the look of it.
      1. LostMarine's Avatar
        LostMarine -
        it does. I tried to show just how good it is when shifting before redline in M as thats where we make our money, but i forgot to on that run and then had no time/road to repeat. there will be more to come, but on more boost as well
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by LostMarine Click here to enlarge
        I havent done anything to add to cooling. Ive got about 300 miles on it right now.. Im gonna go back up there soon for software changes and ill see about adding an external cooler
        What software changes will they make?
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        What software changes will they make?
        again, i dont know what needs to be done. just a few things i would like improved upon, but they couldnt do it at the time.
      1. fundahl's Avatar
        fundahl -
        That car is like, "100, when?"

        Those autos are so smooth!

        Can't wait to get my meth kit in..... and some other plans finished in the future...
      1. mazdaspeed6's Avatar
        mazdaspeed6 -
        I just $#@! my self, I forgot how fast you get to 130 with rb's Click here to enlarge hate my life
      1. LostMarine's Avatar
        LostMarine -
        lol.. that was slow by my math.. im about to go setup my map 6 again (lost all saved settings when updated and didnt have that option set on the JB Click here to enlarge )
      1. BattaM3's Avatar
        BattaM3 -
        Where you get your meth from LM? Is 100percent?
      1. LostMarine's Avatar
        LostMarine -
        i go to ATco now, its so close and so cheap, but what i have in now was just leftover for a few weeks and was already mixed. $4/gal there, yes its 100%, VP M1
      1. Yukohama's Avatar
        Yukohama -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        The stall speed of the torque converter. Basically when you step on the brake and the gas there is a stall RPM, right? Well, this RPM is now higher.
        Click here to enlarge Originally Posted by SlicktopTTZ Click here to enlarge
        It doesn't have to do with the gas and the brakes. That would change based on your braking system. But having a higher stall does have an effect on that.

        Here is a good explaination from a Ford forum:

        The stall speed of a converter is determined by several things. A converter is made up of 4 parts, the front cover, stator, impeller, and rear cover. Each part has fins inside it to direct the fluid around each part and by modifying these fin's angle, it changes the stall speed. Stall speed is essentially when the engine speed and fluid speed are the same, and stall speed is NOT when you're sitting at a stop and mash the gas while holding the brake. That rpm is NOT the stall speed, that's just where the engine torque overpowers the brakes and moves the car forward.
        A higher stall speed allows the engine to get into the powerband quicker, like revving a clutch and quickly slipping it. Unlike a clutch, a converter doesn't get grabby or tempermental. But a higher stall speed creates more fluid slippage inside it, creating more heat so an auxiliary trans cooler should be considered mandatory.
        A higher stall speed can also take the shock out of the drivetrain when the trans shifts, making it actually easier on parts.
        The stall speed can also be affected by the engine it's behind. A converter that stalls at 2000 behind a stock small block could stall at 3800 behind a big block. This is why converters should be custom made for your combination for the best performance.
        awww okok i see, thanks guys!
      1. oddjob2021's Avatar
        oddjob2021 -
        thanks for the vids lm, seems like its working out very well, im glad. its funny how you get used to the speed huh? 16psi is slow now lol
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by oddjob2021 Click here to enlarge
        thanks for the vids lm, seems like its working out very well, im glad. its funny how you get used to the speed huh? 16psi is slow now lol
        lol, yeah
      1. enrita's Avatar
        enrita -
        is the oil pan still in plastic or do they change it with one in alu?

        From this picture is in metal but maybe its just a general picture:
        Attachment 8676
      1. LostMarine's Avatar
        LostMarine -
        genera pic., they used a new oem one, as the ring is part of the pan and should be replaced onece take off