MS3 Tach In - Crank Position or Engine Speed?

[planet]

Hello

Im just trying to figure out which of the two i require for the 'Tach in" Input.
This is being set up for a 2002 WRX, going off the ECU pinout there is a Crank Position Sensor signal and also a Engine Speed (RPM) signal.

Here is a link to the pinout if you would like to look
https://www.xcceleration.com/pinouts/20 ... inouts.pdf

I would like to think that the Crank sensor is the way to go, just want to be sure thats all.

Thanks in advance.

[elutionsdesign]

Crank position sensor, rpm is likely an output to the factory tach.

[Matt Cramer]

Use both the crank position and cam position sensors.

[planet]

Okie doke thanks for that.
I might wait till i get the expansion board before i do the Cam sensor. Ive run into a bit of trouble wiring up the LED spark, as soon as i turn the ignition a spark lets go and the car jolts.
I was able to test each spark output successfully but still no luck when i turn it over.

I think im better off waiting for the MS3X board to arrive.

Thanks guys.

[planet]

Turns out the 36-2+2 Trigger is the correct one for my car not the 36-2-2-2.
Tried starting it with nil joy, it was firing here and there but i dont think the coils were having fun, i could smell them getting very hot. Gave them a feel and all of them except for one were very hot. I feel that it was #4 that wasnt, i dont think i wired that one up correctly.