1995 VW Golf VR6 turbo


16VT’s involvement: Spec’ed the engine and turbo hardware; wired in Megasquirt ECU in a plug and play fashion and calibrated fuel, ignition and idle; installed HKS EVC for boost control.


Chassis: FK springs and dampers, No-brand 17x7.5” wheels;

Forced induction: Holset HX40, Audi external wastegate with stock spring, EIP-style split-pulse exhaust manifold, aftermarket 2.5" FMIC, 3” downpipe, 60mm intercooler piping, HKS EBC, HKS blow off valve, 1.0+ bar of boost.

Engine: 2792cc, AAA engine code, 12 valve, free-flow filter & exhaust, C2 spacer to lower CR to 8.5

Injection: Port injection, 440cc/min Delphi HighZ injectors, Motronic ECU, 60-2 trigger wheel, variable reluctance crank sensor, PWM 2-wire bosch idle valve, Bosch coolant and GM intake temp sensors, coilpack with integrated module driving 3 coils in wastespark mode

Description: The objective of this install was to use the original wiring loom. To do this, an old 68 pin ECU was cannibalised and turned into an adapter. The MS was installed inside the car, with wires running to the 'ECU' box. All the original sensors and actuators were used. Shielded wires were used for the VR sensor.

MS v3 internal mods included using the CPU outputs directly to drive the VAG ignition module (+5V to trigger coil), with a 330ohm resistor placed inline to limit current drawn from CPU. A TIP122 was installed to PWM control the 4 ohm idle stability valve. Bias resistors were replaced with 2.2k 1% ones to suit Bosch sensors.

To make the install compatible with the VAG relays, the following was done:

  1. The ISV was fed +12V by jumpering a wire from T68/23 over to T68/27 through a 10A fuse to provide power to the idle valve.
  2. A relay was used to ground T68/9 when ignition was switched on. Grounding T68/9 allows the ECU relay to come on and feed the injectors, ISV and megasquirt through T68/23.
  3. Attempts were made to ground T68/28 in order to enable the O2 sensor relay, but these were not successful and the O2 sensor heater was abandoned early on.


Pin configuration:

MS GROUNDS (8,9,10,11) go to T68/1, T68/7, T68/55, T68/56, T68/58

MS SENSOR GROUND (19) goes to T68/33

MS MAT (20) goes to T68/36

MS CLT (21) goes to T68/14

MS TPS SIGNAL (22) goes to T68/40

MS O2 SENSOR SIGNAL (23) goes to T68/20

MS TACH IN aka VR+ (24) goes to T68/67

MS VR- (7) goes to T68/68

MS TPS Vref (26) goes to T68/41

MS coil A (36) goes to T68/8

MS coil B (25) goes to T68/52

MS coil C (27) goes to T68/60

MS +12V (28 ) goes to T68/23 through 5A fuse

MS FIDLE (30) goes to T68/53

MS INJ1 (32,33) goes to T68/2, T68/4 and T68/25

MS INJ2 (34,35) goes to T68/3, T68/24 and T68/26

MS FUEL PUMP (37) goes to T68/6


Options included:


MS Ouput 2, JS3 - pin 4, SPR2, driving Autometer shift-lite through TIP102 (white wire)

MS Nitrous output JS1 on DB37- pin 5, SPR3, driving ZTX450 (green wire)

MS BOOST control on DB37- pin 6 routed through T68/31 (hence to charcoal canister), unhooked

MS Tacho out DB37- pin 29 was fed to T68/22 to drive cluster using JS0 jumper



Crank signal was decoded using MSnS-E 029a. 60-2 wheel, with 14th (15th if 0 and 1 are the missing teeth) tooth at TDC. Trigger angle 60*. Trigger position A was 5, Trig pos B 25, Trig pos C 45, Trig return pos A 14, Trig return pos B 34, Trig return pos C 54. Spark output was INVERTED since the VW module goes from 0 to 5V when it wants to trigger the coil. Using 3ms on the MS for now.


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