Sold By SSSQUID SKU: CHP-M20B27 Categories: , Tags: , , , ,


IMPORTANT! We NEED to know if you are running a 24 or 28-pin ECU before we can ship an appropriate chip! Please see the FAQ below for more information.

Bring your M20 to life with this fully tuned, daily driven, and track tested  performance chip. The SSSQUID performance chip is the most complete tune on the market, with every aspect of the mapping being optimized from idle to wide-open-throttle.

This chip is compatible with:

  • 1984-1987 BMW E30 325e
  • 1984-1988 BMW E28 525e/528e


  • How do I know if my ECU is 24 or 28 pin?
    • Unfortunately there is no way to tell without opening the ECU and looking at the installed chip/socket.
  • I want to upgrade injectors. What do I do?
    • You MUST run low-impedance injectors. The 325e ECU uses an outdated injection control system that is not compatible with most every injector manufactured after 1985. Unfortunately, this means that there are very few plug-and-play injector upgrades for the 325e.
    • The 325e utilized low-impedance injectors, whereas most every injector that fits into the rail will utilize a HIGH-impedance system. A low-impedance injector gets a current of 5-6 amps, whereas a high-impedance injector will receive a current of only around 1 amp.
      • Putting 6 amps of current through an injector that is only designed for 1 amp means the injector may fail quickly and will likely not flow correctly.
  • I have M50 injectors (17.5 lb/[email protected], or aprx. 12.5 lb/hr on the M20B27 2.5 bar), will they work?
    • They will not work. Please see the above question about impedance.
  • TURBOCHARGER: I want to turbo my 325e!
    • While it is possible to turbo the 325e with a few changes, the stock ECU is very limited and the electronics limit your injector choice to pretty much just the stock injectors. The M20B25 or M30B35 ECUs are much more capable and are able to handle medium levels of boost quite well.
    • If you choose to stick with the stock 325e ECU, we do recommend using a RRFPR. A ratio of 6:1 or 8:1 would be ideal for 8psi.
    • Ideally the VAM (AFM) will be placed as a draw-thru, but if you must place it as a blow-thru we can tune for that as well. However, as a blow-thru it does harm some scalability and smoothness.
    • We HIGHLY recommend upgrading to the Motronic 1.1/1.3 electronics if possible, but it’s not a strict necessity.


0.5 5300
1.0 5500
1.5 ++
2.0 ++
2.5 ++
3.0 ++

++ Denotes modification-specific limits. We will recommend a rev limit based on your engine modifications, but it can also set according to your request!

Don’t know what stage you need? Looking for a little advice? Please see the GETTING STARTED page or CONTACT US for more information!


Shipped and sold directly by SSSQUID!

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