Logging OBD-II?

[carcrazy]

Any new news?

[RTUSA]

No, it's still in the development queue, but I'm pushing from the sales side!

[felix]

Any updates?

[RTUSA]

Happening hot and heavy as I type, nearly done I think.

[kartaphilos]

Do you have an idea of release date?

Ta,
Matt

[RTUSA]

As a guess, about 2 months.

[Herbert]

I want! Price permitting... For '99 Corvette and/or '08 Corvette. Any idea how much post-processing / reverse-engineering of the logged data is needed? If it's all up to the user, any pointers to info on how to do this?

[RTUSA]

Pretty easy from the user side, the data comes in (from the adapter) as normal Race Technology data, so it shows up in Monitor, Analysis, DASH etc. just by selecting the elevant channel.

We are currently in test/debug with this, so it's coming along nicely.

[Herbert]

Can you elaborate what data would be available via this interface? Would it be RPM, throttle position, brake on/pressure? Wheel speeds? Steering wheel angle? Maybe even suspension travel? I'm pretty sure the Corvette has sensors for all this, but I don't know which of those are available via its OBD-II port.

[jlucas]

Herbert, OBD2 would have stuff like rpm, oil temp, water temp, instake temp, even throttle position. A google search would probably give you a complete list. For stuff beyond that, you would need a CAN equipped car and know what the CAN channels are (don't know if GM publishes that info or if Pheonix knows). I don't know what year they switched to CAN on the C5 but my understanding is that the later ones are CAN. I've seen CAN data from Bosch controlled German cars and all that stability control info is in there (steering angle, yaw, etc...).

[markv]

Please don't forget OBD has limited speed on which it delivers information. With the normal publicly available interface (so not manufacturer specific) you're very lucky if you get up to 7 samples per second if only monitoring 1 variable. So monitoring 2 would get you 3.5 per variable etc.

You can get higher speeds, but usually you need to know manufactorer specific requests to send and be able to decode the data. On my E15 ecu I can get around 3 samples per second for about 80 variables, but that is with a specific command and it violates the official packet lenghts afaik.

Oh, and using CAN is no guaranty for higher speeds. Data may be transported faster, but that doesn't mean the ECU will give higher priority to sending the data...

Mark

[RTUSA]

Mark:

What we are doing is grabbing data at various rates, ie RPM and throttle position at highest priority, things like coolant temp and lambda trim at low priority.

So though it could be quicker, it's pretty useful info in my opinion.

[ZEDohSIX]

My original intent was to get access to steering, throttle and brake position so that I could finally do some slip calculations and few other things. However it appears that the data may not be fast enough to actually be useful.

Maybe I just should have bought string pots two years ago. It seems like that is still my best option.

[RTUSA]

Z06:

We are initially reading only the "generic" OBD2 info, which I don't think will include steering angle and probably not brakes. Throttle will be there.

We will also have a pure CAN interface, which can be programmed to read anything that's available on the CAN bus. Caveats are that you have to have the CAN data parameters - which are not generally published - and of course you need to have a CAN based car.

[tristancliffe]

and of course you need to have a CAN based car.

If you don't, does that make it a CAN'T based car