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martsink · 04-23-2015, 10:52 AM

Hi guys,
I'm trying to work out how to make the Boxster tach work with my LS V8 conversion. The new GM engines all use 58X reluctor wheels which are just plug and play with the Porsche tachs, but unfortunately my engine is 24X. The LS1 ecu spits out a 5V square wave at 2 pulses per revolution. Does anyone know what kind of signal is fed into the Porsche tach?

I guess if all else fails I can make some optical arduino tach or maybe do what this guy did on his Lotus swap:

4.2 V8 ABZ conversion of Lotus Esprit :: motorgeek.com

04-23-2015, 10:52 AM	#1
martsink Registered User Join Date: Dec 2014 Location: SF Bay Area Posts: 246	986 Tach Signal Hi guys, I'm trying to work out how to make the Boxster tach work with my LS V8 conversion. The new GM engines all use 58X reluctor wheels which are just plug and play with the Porsche tachs, but unfortunately my engine is 24X. The LS1 ecu spits out a 5V square wave at 2 pulses per revolution. Does anyone know what kind of signal is fed into the Porsche tach? I guess if all else fails I can make some optical arduino tach or maybe do what this guy did on his Lotus swap: 4.2 V8 ABZ conversion of Lotus Esprit :: motorgeek.com