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Vq25det Tach Rpm Signal


datmoo
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Just fitted an Innovate SCG-1 and wanting to know the best place to pick up a tach signal for the shift light/rpm log function.

Waiting to hear back from Innovate regarding what voltage/pulse/frequency it needs to see.

Here's the spiel from the manual: Optionally, the PURPLE wire can be connected to a tach signal to log engine RPM and to use the shift light function. A tach signal can be acquired from the negative lead of a coil, ECU, negative lead of an injector, or directly from the ignition box if running a multi-spark (i.e. MSD 6AL). Note: A tach signal can not be acquired from the negative lead of the coil on vehicles running CDI ignitions. For these applications use the negative lead of an injector or a tach adapter (if available for your model ignition).

I had to use an Autometer tach adapter in my SR 1600 to get the VDO tach to work but my Gizzmo shift light worked fine off the ECU tach wire. I did find pin 34 on the M35 ECU is "Engine Revolution Output Signal (to Hicas C/U)".

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I would go strait from the injector or the ECU rpm signal wirend

Spot on Nathan. Took it from number 1 injector (easiest to get to) red/black wire. Set the SCG-1 to 10230 RPM scale and 2 pulses per rotation even though the Innovate software says 3 pulses for 6 cylinder. Shows 630 RPM at idle and stays very close to the factory tach needle. Shift light all good. Still playing around with all the fine adjustments; duty, gain, spring pressure and boost cut by pressure and AFR. Easy enough to adjust with the gauge but also downloaded the programming and logging software and had a play around using the laptop. Nice bit of kit, think I'll get another one for my Datto and get rid of the boost T.

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Spot on Nathan. Took it from number 1 injector (easiest to get to) red/black wire. Set the SCG-1 to 10230 RPM scale and 2 pulses per rotation even though the Innovate software says 3 pulses for 6 cylinder. Shows 630 RPM at idle and stays very close to the factory tach needle. Shift light all good. Still playing around with all the fine adjustments; duty, gain, spring pressure and boost cut by pressure and AFR. Easy enough to adjust with the gauge but also downloaded the programming and logging software and had a play around using the laptop. Nice bit of kit, think I'll get another one for my Datto and get rid of the boost T.

Nice! Looking at getting one of these myself. Got my tune coming up on Friday and then the move up to Brisbane in April so I'll have to hold off for a while. Was the install fairly simple?
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Nice! Looking at getting one of these myself. Got my tune coming up on Friday and then the move up to Brisbane in April so I'll have to hold off for a while. Was the install fairly simple?

Not too difficult. Probably the most time consuming thing was working out where to mount things, how to route the hoses/cables and getting them through the firewall grommet. Got mine through www.kadespeedandmarine.com.au in QLD, you'll be able to save on postage when you move.

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Not too difficult. Probably the most time consuming thing was working out where to mount things, how to route the hoses/cables and getting them through the firewall grommet. Got mine through www.kadespeedandmarine.com.au in QLD, you'll be able to save on postage when you move.

goid to know thanks mate yeah I'll save it till I'm up there in that case defiantly! I'm going to organise a Brissy meet if your intrested in say may early June so I can get to know all the m35 crew up there!
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