Logging standard ECU map ignition timing?

Logging standard ECU map ignition timing?

Author
Discussion

NISaxoVTR

Original Poster:

268 posts

168 months

Monday 15th September 2014
quotequote all
I'm looking at swapping the standard ECU on my MG ZS 180 to an aftermarket ecu, probably a KMS. The KV6 isn't a popular engine among tuners so a base map is hard to come by. Rather than start from a blank sheet is it possible to use a data logging device to record the ignition and injector timings from the standard ecu? Has anyone done this before and what logging tool did you use? If not possible to capture the whole map it would be great even just to get the typical idle/cruise/full throttle timings.

DVandrews

1,315 posts

282 months

Monday 15th September 2014
quotequote all
The volumetrics and CR of the 2.5 are similar to the 1800 K series, so I wouldn't expect the advance curve to be that different. I have a number of ignition maps kicking around for 1800Ks , one of these would probably give a decent starting point.

Dave

anonymous-user

53 months

Monday 15th September 2014
quotequote all
Pretty sure you can fairly easily log ignition angle from the OBD port using a generic K-line interface. Also, i bet you could easily upload the contents of the std ecu EEPROM and find the ignition and vol eff tables pretty easily.

DVandrews

1,315 posts

282 months

Monday 15th September 2014
quotequote all
The only values you would get would be those for the load/speed sites you traverse and I'm not sure that the Rover ECU is that straightforward to interrogate.

Dave

anonymous-user

53 months

Monday 15th September 2014
quotequote all
It's got EOBD, and "ignition angle" is one of the necessary mandated PIDs. And of course, you only care about the bits of the map you can get too........... ;-)

DVandrews

1,315 posts

282 months

Monday 15th September 2014
quotequote all
Who says you can't get to them? It will depend on prevailing conditions and they are bound to go well beyond the sample you eke out. My experience of talking to Rover ECUs shows them to be recalcitrant at the best of times.

Dave

anonymous-user

53 months

Tuesday 16th September 2014
quotequote all
DVandrews said:
My experience of talking to Rover ECUs shows them to be recalcitrant at the best of times.

Dave
That's because they talk with a brummie accent i think.......... ;-)

NISaxoVTR

Original Poster:

268 posts

168 months

Tuesday 16th September 2014
quotequote all
I've heard comparisons between the 1.8 and 2.5 before Dave, I'd be interested to see the ignition table for one. If you're familiar with them do you know if the pistons are interchangeable? I've seen liners being sold for 1.8 or 2.5. As for getting the factory ignition times it sounds like you will have to talk to the standard computer? I was hoping there would be something like a piggyback ecu that you could wire in to the crank/injector/coil and record the map as you drove, but googling hasn't brought up much.

I don't know much about talking to factory ECUs but it sounds then like they should offer some basic information on a standard protocol and one of those may or may not be the ignition timing in real time?

What kind of software would you need to access the computer, would something like http://freediag.sourceforge.net/ work?

anonymous-user

53 months

Tuesday 16th September 2014
quotequote all
NISaxoVTR said:
I've heard comparisons between the 1.8 and 2.5 before Dave, I'd be interested to see the ignition table for one. If you're familiar with them do you know if the pistons are interchangeable? I've seen liners being sold for 1.8 or 2.5. As for getting the factory ignition times it sounds like you will have to talk to the standard computer? I was hoping there would be something like a piggyback ecu that you could wire in to the crank/injector/coil and record the map as you drove, but googling hasn't brought up much.

I don't know much about talking to factory ECUs but it sounds then like they should offer some basic information on a standard protocol and one of those may or may not be the ignition timing in real time?

What kind of software would you need to access the computer, would something like http://freediag.sourceforge.net/ work?
EOBD / OBD-II (which stands for European On Board Diagnostics / On board Diagnostics - II) is a std architecture for communicating with the engine ecu in all cars. In the case of the motorola ecu used by MGRover, it uses what is called "K line" hardware protocol. Plenty of serial to K line adaptors are available to allow you to connect your PCs serial port (or virtual serial port over USB for modern pcs that don't have the old 9 pin dsub hardware serial port any longer).

Any std OBD scan tool should also be able to report the basic EOBD parameter set, which is mandated, see OBD PIDS


This is the easiest way of getting the information you require, imo.

Alternates would be:

1) to use a universal counter which can report "Phase" information between two signals, and connect that to the ignition coil and the crank sensor. This can then be set up to record the ignition firing angle. This is complex however, due to the differing trigger voltages and signal types, so isn't recommended

2) To physically open your ecu, and use a std EEPROM reader to upload the contents of the memory, which you will have to sift through to find the ignition map. Again, possible, but not that easy and time consuming.


anonymous-user

53 months

Tuesday 16th September 2014
quotequote all
NISaxoVTR said:
What kind of software would you need to access the computer, would something like http://freediag.sourceforge.net/ work?
It says K line, so it should work, but often these programs can be a bit flakky, as they aren't developed to the necessary stds. I'd ask on the Rover forum what people are using for OBD access!

DVandrews

1,315 posts

282 months

Wednesday 24th September 2014
quotequote all
NISaxoVTR said:
I've heard comparisons between the 1.8 and 2.5 before Dave, I'd be interested to see the ignition table for one. If you're familiar with them do you know if the pistons are interchangeable? I've seen liners being sold for 1.8 or 2.5. As for getting the factory ignition times it sounds like you will have to talk to the standard computer? I was hoping there would be something like a piggyback ecu that you could wire in to the crank/injector/coil and record the map as you drove, but googling hasn't brought up much.

I don't know much about talking to factory ECUs but it sounds then like they should offer some basic information on a standard protocol and one of those may or may not be the ignition timing in real time?

What kind of software would you need to access the computer, would something like http://freediag.sourceforge.net/ work?
Sorry, I missed this response, the pistons are not interchangeable, the KV6 are taller (and the better for it), the liners are the same, the heads are basedoin the pattern of the VHPD head (VVC chambers, ports and valve size). If you send me a mail I can send you a screenshot of the ignition map for a relatively stock 1800. It may help.

Dave