Autosport Labs

Whats the recommended method for tapping into sensors that are part of the vehicle? For instance I am trying to get RPM, TPS, and boost pressures to start. I do know the pin numbers on the ECU where the data is going to but what method is best for tapping into those wires?

Anyone? I know on my particular vehicle the RPM signal out that goes to the tach is pin 58. Should I use a T Tap like http://www.amazon.com/Install-Bay-3MRTT ... ords=t-tapon that line and then just run that directly into the racecapture pro, or do I need to pass it through some other circuit? From what I've seen this is the wire that people tap for shift lights and it seems to be a direct connection in that case.

Hi Duncan,

This is a 2 part answer.

Analog sensors:

For analog sensors the universal answer for data acquisition systems in general is to have dedicated sensors since connecting another device up to an existing sensor can 'drag down' the signal and effect the reading the ECU sees. RaceCapture/Pro has generally the same requirements as other systems, so we recommend dedicated sensors for best results.

We have a growing sensor database - feel free to check this out and let us know if there's anything that should/could be added:
http://www.autosportlabs.net/RaceCapturePro_Sensors

In some cases you may be able to tap into the *gauge sensors* depending on their design. this is what we experimented with during the race this weekend. Each gauge / sensor combination is different so results will vary.

What we are doing is working on creating a convenient list of sensors and Race Capture calibration data so it's much more plug and play. Stay tuned!

Tach sensors:

For tapping into the tach signal: there are two different kinds of signals present on ECUs. Some systems tap right into the ignition coil primary circuit, which has a high 400-500v high voltage spike which can damage electronics. RaceCapture/Pro is not designed to handle such an input as the inputs are protected to 40v, so do not connect the tach signal without knowing the source.

We have designed (and are testing) a small opto-isolated adapter board for buffering and conditioning that signal. More information on that coming soon.

The other forms of RPM signals present are a 5v logic level signal often seen on newer ECUs. Intelligent coil on plug modules that are driven by a 5v signal can be a good source for a tach input on race capture.

Do you know what kind of tach signal is available on your engine?

From what I've been told at evom the tach wire that comes out of my ECU goes directly to the cluster, and as long as i leave my stock cluster in I should be ok for tapping the wire and running into to the data logger =D

Is your ECU OBD2 ?

Search for ELM327 on the web !)

Yeah, It is ODB2 and MUT-II compliant so since I got the bluetooth addon coming i'm just going to wait and log that info through there. Sadly I don't think it will let me log boost pressure that way but I'll find an alternative.

Brett, what do I do to hook up a Autometer Tach, I have a non ecu GM running an HEI.