extending map connection

[Nismo280zEd]

We are starting the 911 MS project, We are trying to use 6 COP with 6 VB921 to drive each individual coil, although we might have to resort to wasted spark and run 3 VB921. Anyway.... 911 the motor is in the rear and the ECU is under the driver. Does anybody forsee a problem with moving the MAP sensor from on the board to closer to the engine for a shorter vacumn line and less pressure drop. Basically running wires off the board to the sensor.

[olie05]

From the megamanual:

Note: if you do not like the idea of mounting the MAP sensor on the PCB in the passenger compartment, and the long vacuum hose, because you feel it will cause a delay in engine response, you can remotely mount the MAP sensor. Bruce has tested this with about 30 feet of 1/8" tubing and almost no lag, certainly no more than 1 millisecond.

 

If you mount the MegaSquirt inside of the passenger compartment (inside firewall), then the length of tubing is only about 3 - 4 feet. Additionally, if one figures that many MAP sensor installs have the sensor mounted on the firewall on the passenger side near the heater core (many General Motors, Toyota, Nissan, etc. do this), then compare the extra length of tubing to go through the firewall to the MegaSquirt, it is not a large difference.

 

If you want to remotely mount the MAP sensor, use one of the unused connector pins for the MAP signal, there is Vref and ground coming out already for the TPS which you can share with the MAP sensor. The V2.2 boards have jumper "holes" to the output connector unused pins - you can use one to bring the MAP signal out quite easily. If you do remote-mount the sensor, be sure not to put any type of strain on the MAP sensor case - according to Motorola this can introduce DC offsets in the readings.

 

I'm with the first paragraph on this one.