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root
09-01-2003, 02:31 AM
I have a 95 Toyota 4x4 that I installed a 350 with msd 6 offroad ignition box,I also pickup the 8920 tach adapter.I not sure if the factory tach is voltage or current triggered.Voltage triggered is hook to neg of coil and current triggered off the posi side of coil,what I can see ,it look like it is hook to the igniter on posi side NOT SURE,if anyone out there could let me know that would be great.Thanks again

msdtech2
09-01-2003, 12:47 PM
Current trigger tachs are normally on older style vehicles, although for your application, I will have to look at a factory diagram, it may be possible that the trigger wire comes of the igniter. I will let you know for sure on Tuesday.
Thanks,
msdtech2

msdtech2
09-02-2003, 11:09 AM
The factory tach is trigger from the igniter, so your best bet is to connect to the tach output of the MSD Unit to see if it will read properly. Some of the factory tachs are normally calibrated to the number of cylinder to the original engine, so you may have to get them recalibrated to an 8-cylinder application. I do not know of a company that will do this type of calibration.
Thanks,
msdtech2