• PPM-Racing (Pure Performance Motorsport) 4.2 liter S38 inline-6 stroker kit - $6900

      The BMW S38 is one of (if not arguably the best) the most impressive inline-6 cylinder motors ever produced by BMW. We will leave that debate for another article however and instead give you the details on the PPM-Racing 4.2 liter stroker kit. It includes forged pistons, H-Beam connecting rods, and a billet 4340 crankshaft. It is applicable to either 3.6 or 3.8 liter S38 motors from the BMW E28 M5 and BMW E34 BMW M5 respectively.

      The kit can be customized and accommodate naturally aspirated or boosted builds with compression ratio choices for the pistons including 8.0:1, 8.5:1, 10.0:1, 11.5:1, or 12.0:1. Piston sizes are either 94.5 or 95.0 mm. The kit is designed to use a 1x compression ring. Awesome? Yes, awesome.

      Pricing: $6900

      Included:

      - 6x forged pistons
      - Rings, pins, locks
      - 6x H-Beam connecting rods
      - ARP2000 rod bolts
      - 98mm Billet 4340 crankshaft





      This article was originally published in forum thread: PPM-Racing (Pure Performance Motorsport) 4.2 liter S38 inline-6 stroker kit - $6900 started by Sticky View original post
      Comments 60 Comments
      1. LostMarine's Avatar
        LostMarine -
        Any power figures?
      1. Sorena's Avatar
        Sorena -
        germanboost.com/showthread.php?995-PPF-E30-S38-Turbo&p=11396#post11396
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Can't the S38 go to 4.2 liters or so?
        Haha. Are you prophet or what? lol
      1. DBFIU's Avatar
        DBFIU -
        Holy $#@! this is awesome, the inline six is bigger in displacement than an S65. I would make this thing 12:1 compression all motor and rev the $#@! out of it.
      1. fundahl's Avatar
        fundahl -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        Holy $#@! this is awesome, the inline six is bigger in displacement than an S65. I would make this thing 12:1 compression all motor and rev the $#@! out of it.
        Or the same but with 8:1 compression with a one of the T4 EFR choices and throw as much boost as it can take. Probably would have one of the fattest/fastest spooling I6's around!

        E85 for fueling of course. Or methanol if you are the drag racer 2000HP type. Click here to enlarge
      1. DBFIU's Avatar
        DBFIU -
        ^ thats cool and all but a 4.2 liter inline 6 with 12:1 compression at 8500 RPM sounds so nice!!!

        Turbos shmurbos
      1. radasaurus's Avatar
        radasaurus -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        ^ thats cool and all but a 4.2 liter inline 6 with 12:1 compression at 8500 RPM sounds so nice!!!

        Turbos shmurbos
        I have a feeling it wouldn't last long at 8500 rpm...
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        Holy $#@! this is awesome, the inline six is bigger in displacement than an S65. I would make this thing 12:1 compression all motor and rev the $#@! out of it.
        13:1 e85 all motor 8k aggressive cams $#@! ya
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by radasaurus Click here to enlarge
        I have a feeling it wouldn't last long at 8500 rpm...
        You wouldn't last long at 8500 rpm.
      1. metrik's Avatar
        metrik -
        What cylinder head types are available for this motor? Non vanos, single vanos, dual vanos?

        The reason I ask, is I think I remember hearing someone say that either this engine was available as a vanos motor later in its lifetime, or a later engine's cylinder head with vanos fit on the engine.
      1. metrik's Avatar
        metrik -
        Click here to enlarge Originally Posted by metrik Click here to enlarge
        What cylinder head types are available for this motor? Non vanos, single vanos, dual vanos?

        The reason I ask, is I think I remember hearing someone say that either this engine was available as a vanos motor later in its lifetime, or a later engine's cylinder head with vanos fit on the engine.
        Looks like I was making things up, VANOS never touched these motors. @Sticky, I'd love it if you wrote an article about this motor, like the excellent one you did on the s54 and s65.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by metrik Click here to enlarge
        Looks like I was making things up, VANOS never touched these motors. @Sticky , I'd love it if you wrote an article about this motor, like the excellent one you did on the s54 and s65.
        Those articles are incredibly time consuming. I likely will do a top 5 BMW motors article.
      1. dreikraft's Avatar
        dreikraft -
        thanks $#@!. i just spent a bunch of money already. damnit now this too!
      1. 600whp S4's Avatar
        600whp S4 -
        this is right next to the ford falcon inline six now that this stroker kit is available
      1. radasaurus's Avatar
        radasaurus -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        You wouldn't last long at 8500 rpm.
        what the $#@! is that supposed to mean? The fact is its a VERY long stroke crank on a straight six that has harmonic issues past 7k with the stock crank. I am not denigrating the kit or the idea of an 8.5k rpm 4.2L s38 screamer (which would be awesome), but it's a pipe dream.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by radasaurus Click here to enlarge
        what the $#@! is that supposed to mean? The fact is its a VERY long stroke crank on a straight six that has harmonic issues past 7k with the stock crank. I am not denigrating the kit or the idea of an 8.5k rpm 4.2L s38 screamer (which would be awesome), but it's a pipe dream.
        Didn't mean anything it was a joke. You are right that it is a long stroke and the piston speeds will be high. The S54 has this same issue but has survived 9000 rpm.
      1. radasaurus's Avatar
        radasaurus -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Didn't mean anything it was a joke. You are right that it is a long stroke and the piston speeds will be high. The S54 has this same issue but has survived 9000 rpm.
        I am not aware of any s54s reliably revving to 9000 rpm in something other than a drag race application (where very little time is spent at such high rpm). The piston speeds would not be the biggest problem, but rather the damaging vibrations due to resonance. Even the s54, which was designed for high rpms, suffers when pushed much beyond its stock redline. The s38's harmonic damper is not as robust (especially in the b35 and b36 versions) nor is it designed for the same rpm range.

        Anyway, I'd love to see what numbers this kit puts down in any form. Any word on someone actually building one of these motors? I'm thinking it would go nice with a 6466 - tractor pulling torque.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by radasaurus Click here to enlarge
        I am not aware of any s54s reliably revving to 9000 rpm in something other than a drag race application (where very little time is spent at such high rpm).
        Yes, at full throttle and big power so high stress. It isn't like anyone sits at 9000 rpm in any street application.
      1. jrode34m5's Avatar
        jrode34m5 -
        Any possibility that those issues of high rpm have been fix with this billet crank shaft?
      1. Tom S85B58's Avatar
        Tom S85B58 -
        Click here to enlarge Originally Posted by jrode34m5 Click here to enlarge
        Any possibility that those issues of high rpm have been fix with this billet crank shaft?
        Yes i am sure with billet crank and ppm custom S38 balancer the problem was fixedClick here to enlarge
      1. GG///M3's Avatar
        GG///M3 -
        I vote 8.5.1 turbo setup with a gtx42 turbo redline at a safe 8200 rpms. That thing would have a monster powerband.