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1987 325e sedan M30B35 swap

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    Just for fun I decided to take the car to my local 1/8th mile drag strip. It did not go well.
    I pulled out of the water box, was in the middle of doing a burnout, and the engine died mid burnout. Never even got to stage.
    I got a push back to the pits and attempted to diagnose the problem with minimal tools. Eventually I gave up and proceeded to spectate and kick back a couple of beers.

    I ended up towing my car home hours later.

    Now in the comfort of my garage I could diagnose why the engine died.
    I found my wideband had came un plugged. Apparently I didn't leave enough slack in the harness and when I did my burnout it must of pulled the connectors apart. My MS tune has a 15% EGO correction. It should still run without a wideband.
    Next I checked the timing. I rotated the crank hub to TDC with alternator hub nut. I noticed while I was turning the engine over that the crank wheel was turning but not the crankshaft. EUREKA!
    Apparently I snapped my woodruff key for my crank hub and the ignition system lost timing with the engine.
    After further investigation it was discovered I didn't even have the crankshaft nut. It had loosened at some point and just fell off.
    Fortunately no damage had occurred on the hub or the crank.

    I got a new key and a used nut from my spare stock.

    The torque on the crank nut is something like 300ftlbs. I didn't have a tool to apply that much torque. So I tightened it till the emergency brake could no longer hold the car and tack welded the nut to the crankshaft. That should prevent this from happening ever again.
    I'm going back to the drag strip tomorrow. I'll make another post with hopefully better results.

    Sent from my SM-G960U using Tapatalk


      Made it to the track the other night and had a great time. I probably made 20 passes, many performed back to back.
      Sadly my car is still pretty slow, 9.50 in the 1/8th isn't exactly fast. It converts to a 14.8 in the 1/4.
      Here is my best time.

      Here is a video my friend took, almost beat a poorly driven mustang.
      I'm going to re do my exhaust this week. I installed a Moroso spiral flow muffler when I first built the exhaust and I've read they don't flow great.

      I'm gonna try just replacing it with a straight pipe and just rely on the rear muffler. However if it is too loud I'll install a resonator that looks like it will flow a little better.

      Sent from my SM-G960U using Tapatalk


        How did you go on launch? I struggle to get my car to bite traction even with a 3.15 I still manage too cook 225/50/16 semi slicks

        3” single with a hotdog resonator & resonable sized rear my e30 is LOUD & drones at freeway speed, whilst the rebuilding is taking place I’m redoing the exhaust with with a single 2.5”, centre resonator, & custom headers


          Hate to say it, but my 2.5 inch also drones with a decent sized hot dog resonator and rear muffler. I'm going to try an e46 328i rear muffler I have in the shed at some point.

          I think to avoid drone a twin 2 inch system is probably the best option (but obviously much more expensive).
          My e30: OEM+ with M30B35


            just get the biggest longest muffler you can fit back there.


              I ended up cutting out my moroso muffler.

              It looked pretty restrictive.

              I just replaced it with a 2.5" straight pipe.

              It made the car only slightly louder. It sounded a lot healthier too. I'm only running an auto parts store magna flow muffler in the back.

              Now to take it back to the track, which ended very fast.
              I was in the middle of doing my first burnout and all the sudden something came loose and shook the ever living shit out of the car. I shut the car off immediately and pushed it back to the pits. I'm not sure what had happened at the time, the car still ran but if I gave it any revs the car shook violently. Maybe something in the clutch cam loose?
              I ended up towing the car home later that night.
              I removed the transmission the following night to find this.

              Clearly I had broken some pressure plate straps.

              Never seen straps tear like this before. I've seen them bend, but not tear out completely. This was a stock e28 535i clutch and pressure plate.
              I'm going to replace it with a e24 m6 clutch.

              Sent from my SM-G960U using Tapatalk


                Excellent build, lots of "why didn't I think of that" stuff going on. Can't wait for another video!
                Jah bless! :pimp:


                  Replaced my clutch with e24 M6 clutch. It wasn't cheap.

                  Flywheel still looks in excellent shape.

                  I've been watching a lot of drag racing YouTube videos and got pretty interested in nitrous setups. Kinda playing around with the idea of making my sedan a drag car. I know the e30 is supposed to be a twisty road/track car, but I live in Florida where we only have on/off ramps and straight roads.
                  So I pieced together a nitrous system.

                  My microsquirt has a dedicated nitrous controller built in. I run the nitrous all dry and the microsquirt adds additional fuel and retards timing to whatever values I input. Obviously the injectors will be the limiting factor to how much nitrous I can run.
                  Dry nozzle before the throttle body.

                  With this nozzle and solenoid I can only run a 175hp jet, which should be plenty.
                  Here are some pics of the routing of the nitrous.

                  1 step colder plugs after a few 75whp jet runs.
                  Here are my microsquirt settings for the nitrous.

                  I'm currently running a 125hp shot right now. IT'S INSANE!!! 125hp is about all I can run on the stock injectors. Definitely feels like a 300whp e30 sleeper.
                  The 195 tires on the bottle caps are pretty much useless now.

                  Sent from my SM-G960U using Tapatalk


                    Why not an aftermarket clutch?
                    aftermarket pp has multiple straps and modded to be stronger than an m5 one.

                    the stock m30 ones are pretty decent though i pushed one to 10psi before it started to let go
                    maybe alittle over 300tq.


                      Casual Nos drop in. I love how much you enjoy this car! I envy, very much.
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