95 W140 S600 Coupe V12 M120 Engine
Posted: Tue Sep 09, 2008 4:02 pm
Well if you have ever had the pleasure of owning or working on a W140 chassis car (especially the V12) then you know how expensive the electronics can be. If you are unlucky like me then you know how problematic they can be as well. I dealt with numerous ASR problems and Limp Home mode occured daily. I replaced the electronic throttle bodies and was later told by the same dealer that I needed a new Egas module. That was the last straw. The parts alone were $4800 from the dealer. I am not made of money.
The solution, Megasquirt.
I am running MSnSExtra 1 with the V3.0 Board.
The stock setup uses a 3 tooth crank wheel with 2 VR sensors placed 60* apart on the flywheel. I tied these two sensors together to get a 6 tooth type signal. For tooth counter reset I am using the 2 stock Camshaft VR sensors also tied together. For conditioning the second trigger I am using the LM1815 circuit described in the manual. no modifications were done to the schematics. The crank sensor puts out 1.5Volts at cranking speeds so I had to turn the tigger pot up around 10-12 turns to get the signal stable at running speeds.
For coolant and intake temperature sensors I am using the stock MB units.
The stock injectors were used. They are High Z 16ohm.
The stock twin distributors were used as well as the twin coils. I am triggering them simply as spark A and spark B. The trigger point settings are 1,2,3,4,5,6
The trigger angle is 57*.
The stock throttle bodies were drive by wire type so I eliminated them. I am using a pair of throttle bodies from 2 Ford 4.6L Mod motors and the stock Ford Throttle Position Sensor.
For A/F monitoring I am using the Innovate LC-1.
I have one output circuit built on the proto board for driving a relay to switch the VVT solenoids on and off. The switch points are RPM based and they are on between 2200rpms and 4400rpms.
The stock electric cooling fans are controlled by the automatic climate control computer by the factory so I had no need to control them.
The transmission is pre-electronic version 4speed which is vac modulated.
The ABS system, Adaptive Dampening System, ASR system, were all removed. I did keep the stock ASR computer installed with only a few wires hooked to operate as the VSS buffer. The stock speedo system buffers the left front ABS speed sensor thru the ASR then out to the speedometer. All other control modules were completely removed.
I have the wiring in place for a Ford PWM IAC. I have not needed it so far. I am only in the initial tuning stages and that may change. It is possible though that I won't need it since this car produces over 350 pounds of torque at idle speeds, the A/C compressor doesn't even phase it.
So far I only have the motor idling. I still need to fabricate the throttle cables. I plan on making a bracket which attaches 2 throttle cables to the stock Throttle/Transmission cable adjustment point.
Install pictures will follow soon.
The solution, Megasquirt.
I am running MSnSExtra 1 with the V3.0 Board.
The stock setup uses a 3 tooth crank wheel with 2 VR sensors placed 60* apart on the flywheel. I tied these two sensors together to get a 6 tooth type signal. For tooth counter reset I am using the 2 stock Camshaft VR sensors also tied together. For conditioning the second trigger I am using the LM1815 circuit described in the manual. no modifications were done to the schematics. The crank sensor puts out 1.5Volts at cranking speeds so I had to turn the tigger pot up around 10-12 turns to get the signal stable at running speeds.
For coolant and intake temperature sensors I am using the stock MB units.
The stock injectors were used. They are High Z 16ohm.
The stock twin distributors were used as well as the twin coils. I am triggering them simply as spark A and spark B. The trigger point settings are 1,2,3,4,5,6
The trigger angle is 57*.
The stock throttle bodies were drive by wire type so I eliminated them. I am using a pair of throttle bodies from 2 Ford 4.6L Mod motors and the stock Ford Throttle Position Sensor.
For A/F monitoring I am using the Innovate LC-1.
I have one output circuit built on the proto board for driving a relay to switch the VVT solenoids on and off. The switch points are RPM based and they are on between 2200rpms and 4400rpms.
The stock electric cooling fans are controlled by the automatic climate control computer by the factory so I had no need to control them.
The transmission is pre-electronic version 4speed which is vac modulated.
The ABS system, Adaptive Dampening System, ASR system, were all removed. I did keep the stock ASR computer installed with only a few wires hooked to operate as the VSS buffer. The stock speedo system buffers the left front ABS speed sensor thru the ASR then out to the speedometer. All other control modules were completely removed.
I have the wiring in place for a Ford PWM IAC. I have not needed it so far. I am only in the initial tuning stages and that may change. It is possible though that I won't need it since this car produces over 350 pounds of torque at idle speeds, the A/C compressor doesn't even phase it.
So far I only have the motor idling. I still need to fabricate the throttle cables. I plan on making a bracket which attaches 2 throttle cables to the stock Throttle/Transmission cable adjustment point.
Install pictures will follow soon.