VR4/GGSR Specific RPM question....

[JayRome]

Just need to know if anyone has ever ran an external RPM gauge and or shift light on our existing ignition system? (Autometer/StewartWarner/etc)

Must still be using stock ECU (chipped is okay) and stock coil packs..

Looking to see exactly what type of signal our RPM gauge and ECU needs to see to operate properly..

About to develop something and need some variables filled in..


Any help appreciated..

 

[Ross Cox]

Just need to know if anyone has ever ran an external RPM gauge and or shift light on our existing ignition system? (Autometer/StewartWarner/etc)

Must still be using stock ECU (chipped is okay) and stock coil packs..

Looking to see exactly what type of signal our RPM gauge and ECU needs to see to operate properly..

About to develop something and need some variables filled in..


Any help appreciated..

http://www.ecliptech...id=67&Itemid=69


Cheers
Ross

 

[4piknup]

I cant answer your question. But I did buy a digital storage oscilloscope from ebay. They are the size of a mobile phone and pretty easy to use and portable as well. Mine was about $90 and I use it heaps.
With all the messing around you do with wiring and ecus. You should have one.

Search 'dso' on ebay and scroll down to $70 ish.

If you had one you could pull the waveform directly from the sender.

 

[turbovr4]

I am not sure if this is any help, but I have run a VDO tacho before on the MG when I trialled running the standard ecu and VR4 motor in it before I changed to haltech as I couldn't fit the airflow meter in, the tacho ran fine as long as I connected it to the 4th wire out of the tacho interface plug on the coil packs from a 1G motor, I also had a mate that we put a 2G vr4 motor into a scorpion and initially we hooked up the factory sigma tacho then later ran an Autometer but no shift light, just the base model. On that one being a 2G motor we had to hook it up to the Igniter pack which had an extra wire on the 6 pin plug. Anyway all the tachos I have tried have run but they only connect to the coil low tension side. I think the ECU like the Haltech just gets its signal from the crank angle sensor which is 5Volt square wave as it is an optical pickup.

 

[JayRome]

I cant answer your question. But I did buy a digital storage oscilloscope from ebay. They are the size of a mobile phone and pretty easy to use and portable as well. Mine was about $90 and I use it heaps.
With all the messing around you do with wiring and ecus. You should have one.

Search 'dso' on ebay and scroll down to $70 ish.

If you had one you could pull the waveform directly from the sender.

I have an old one, but it's in storage somewhere...

I am not sure if this is any help, but I have run a VDO tacho before on the MG when I trialled running the standard ecu and VR4 motor in it before I changed to haltech as I couldn't fit the airflow meter in, the tacho ran fine as long as I connected it to the 4th wire out of the tacho interface plug on the coil packs from a 1G motor, I also had a mate that we put a 2G vr4 motor into a scorpion and initially we hooked up the factory sigma tacho then later ran an Autometer but no shift light, just the base model. On that one being a 2G motor we had to hook it up to the Igniter pack which had an extra wire on the 6 pin plug. Anyway all the tachos I have tried have run but they only connect to the coil low tension side. I think the ECU like the Haltech just gets its signal from the crank angle sensor which is 5Volt square wave as it is an optical pickup.

Sweet cheers for that, i have an MG Midget in storage, and i know what that needs for the RPM gauge to work....

cheers guys!