speed sensor pulses to the PCM, how low can you go?
#1
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I've searched for info and only found topics about the 4000 ppm signal generated by the PCM based on signal from the speed sensor.
Has anyone used a 2 or 4 pulse per revolution INPUT to the pcm from the speed sensor, such as using a TH400, TH350 with a cable driven sine wave sensor (allows cable speedo to still be driven)
I know the PCM usually expects 40 pulse per revolution, but will it have any problems with this low of an input? What will the computer generated 4000 pulse per mile signal be doing at this point? Anyone have any input on this?
Different PCM all together, but I did program a 93 LT1 PROM, that expected a 4 pulse per /rev to work with a 40 pulse (91 truck 700R4 tranny), this worked great.
Thanks
Brendan.
Has anyone used a 2 or 4 pulse per revolution INPUT to the pcm from the speed sensor, such as using a TH400, TH350 with a cable driven sine wave sensor (allows cable speedo to still be driven)
I know the PCM usually expects 40 pulse per revolution, but will it have any problems with this low of an input? What will the computer generated 4000 pulse per mile signal be doing at this point? Anyone have any input on this?
Different PCM all together, but I did program a 93 LT1 PROM, that expected a 4 pulse per /rev to work with a 40 pulse (91 truck 700R4 tranny), this worked great.
Thanks
Brendan.
#2
TECH Veteran
iTrader: (19)
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It doesn't ans your question but several sponsors on here including yank have kits for retrofiting and plug and play speedo kit for the TH400 into an f body. This would include the pickup and the excitor ring to be pressed onto the output shaft. the ring is specially made and not generally available. Possibly for other apps too. You may not need the cable driven transducer.