Announcement

Collapse
No announcement yet.

The M30 with lightweight flywheel is crazy fun

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    The M30 with lightweight flywheel is crazy fun

    The M30 is a motor that really requests upgrades to get faster response.

    We built our M30B35 with Getrag 240, 3.64 final gear, RHD flywheel on 3.2 kg / 7.05 pounds plus S38 headers with 2.5 "exhaust.

    The result is incredibly fun! You should raise idle rpm to 1000 rpm because the flywheel is a bit too light, so now the car behaves like angry camshafts at idle speed.

    Enjoy! :)

    https://youtu.be/dmBQz_d1UaI

    #2
    Nice to see a review on the RHD flywheel. I looked into getting one when I had everything apart, but opted to save the money for potential repairs. Although the price was hard to say no to.
    1986 325e Pearl White on Grey Houndstooth 24x,xxx miles M30b35 Swapped
    2002 525i Jet Black on Sand Beige 13x,xxx miles
    "This 2.5 liter inline six cylinder is smoother than my silk Versace underwear." -Vehicle Virgins

    Comment


      #3
      On my car I recently upgraded to a 3.73 rear from a 3.46 (and before that a 3.25). It also has a Getrag 260/6, and an E28 533i flywheel that weighs approximately 15-17 lbs. I have been toying with the idea of one of their 8.5 pound moly units too. I love the responsiveness of the car already and I agree with your assessment of a simple way to really wake up the M30 in a cost effective way.
      Never argue with stupid people, they will drag you down to their level and beat you with experience. -Mark Twain

      Comment


        #4
        I'm glad you posted up about this- if you can, once you get some miles on it, comment on drivability, possibly a video? Are you running an M20 clutch and a regular M30 starter? Is the slave engagement standard? Any shims needed?
        1989 Zinnoberrot M3 Build Thread
        1990 Brilliantrot 325iS Build Thread

        Comment


          #5
          Originally posted by AWDBOB View Post
          I'm glad you posted up about this- if you can, once you get some miles on it, comment on drivability, possibly a video? Are you running an M20 clutch and a regular M30 starter? Is the slave engagement standard? Any shims needed?
          Of course, I'll try to give you some more information!

          We have so far driven about 70-80 miles with the car. In terms of positive vs. negative things, I'll do a list:

          Positively:
          * Very fast response
          * It feels more "alive" than the original M30
          * Relatively easy to get a good clutch
          * Very nice to drive, pulls well from 1000 rpm and feels like a locomotive

          Negative:
          * Idle becomes uneven if idle rpm is at the same rpm as original. You would have to raise idle to 1000 rpm to get rid of this problem
          * At 5-10% throttle at speeds below 2000 rpm, the car may feel jerky because the flywheel does not give so much turning mass

          The only modification was to extend the rod to the slave cylinder by 21 mm / 0.82 inch.

          We use M20 pressure plate, S14 clutch from Sachs Motorsport, M30 starter, M20 slave cylinder, M10 Getrag 240 release bearing.

          Shift rod from E30 320 and prop shaft from E30 320.

          Together with 3.64 in the rear axle, it revs 3100 rpm at 70 mph. You can ride on 5th gear at 35 mph without any problems, at that speed it revs around 1300-1400 rpm.

          At the moment we are waiting for a new radiator hose, but as soon as possible, we can arrange some movie clips while driving to you.

          Comment


            #6
            Great work!

            You may have been able to get around lengthening the slave cylinder rod by using an e21 323i release bearing - it's deeper than the usual one (which is the same on a whole stack of BMWs including the M10 and M20 powered e30s).
            My e30: OEM+ with M30B35

            Comment


              #7
              This makes me all tingly inside, I got my flywheel cut down to like 13 or 14lbs. After riding around in my homie's e34 535i with intake, exhaust, 4 pintle injectors and a mark d chip my only complaint was how reluctant to rev up and down the m30 was. Hope I didn't have too much removed, bay area traffic is no joke.
              Jah bless! :pimp:

              Comment


                #8
                It will be fine - I run the M10 flywheel on my M30 with a heavy duty 215mm clutch, which would be around the same weight and it works well.
                My e30: OEM+ with M30B35

                Comment


                  #9
                  I went ahead and bought one of the RHD ones to try on the race car. We’ve been running their M20 one on another car and it’s so rev happy!


                  Sent from my iPhone using Tapatalk
                  1984 Alpina B6 2.8/1 #35
                  1991 325i MT2 Touring (JDM bro)
                  1991 Racecar (Chase Schmidt's former drift car - M30)
                  2006 BMW X3
                  2011 Audi A3 - wife's other German car

                  Comment


                    #10
                    Just bought one of their M50HD flywheel to go with the E34 M5 clutch kit. Will be installed on an M44 Z3. Total clutch/pressure pate/flywheel weight is 25lbs. 240mm vs 215mm.

                    Comment

                    Working...
                    X