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martsink · 09-23-2015, 09:26 PM

I've also been trying to get the tach working. Unfortunately for me, all the older LS based engines use a 24 tooth reluctor wheel to keep track of the crankshaft speed and position (LS3 uses 58x. Lucky you!). The Porsche engine uses a 58X reluctor, meaning I cannot just plug in the GM sensor into Porsche DME. The other option is to use the tach output signal directly from the ECU. Unless both engines have the same number of cylinders, this will not work without some modifications to the signal. I've got something worked out with Arduino, but I still have to test it in the car. If you are interested, you can see more on this in my blog.

09-23-2015, 09:26 PM	#78
martsink Registered User Join Date: Dec 2014 Location: SF Bay Area Posts: 246	I've also been trying to get the tach working. Unfortunately for me, all the older LS based engines use a 24 tooth reluctor wheel to keep track of the crankshaft speed and position (LS3 uses 58x. Lucky you!). The Porsche engine uses a 58X reluctor, meaning I cannot just plug in the GM sensor into Porsche DME. The other option is to use the tach output signal directly from the ECU. Unless both engines have the same number of cylinders, this will not work without some modifications to the signal. I've got something worked out with Arduino, but I still have to test it in the car. If you are interested, you can see more on this in my blog. Last edited by martsink; 09-23-2015 at 09:39 PM.