Cam sync/Secondary trigger [was: confused RE: V8 sequential COP outputs]

[smurfinator]

Hombres,
I've been running for a year now using dual-out with the COP on my Audi ABZ V8.  I've finally sorted the cam trigger, but cannot find any reference in the wiki of how I am supposed to select my megatune ignition outputs for full COP.  I tried several likely arangements and got no start.

Anybody?  I have firmware 1.0.73 (with manual h[2] format change), 60-2 wheel and now cam sinc...

It seemed quite simple until the car refused to start :\

[rob@vems.co.uk]

Okay...

What pins are your coils connected to, and what is your firing pattern?
What secondary trigger config value are you using?

Rob

[smurfinator]

Okay...

What pins are your coils connected to, and what is your firing pattern?
What secondary trigger config value are you using?

Rob

coils are wired as A-H = 1-8
firing order is 1-5-4-8-6-3-7-2


My dual out configuration looks like this (running fine)



Thanks for any info!
Ben

[rob@vems.co.uk]

First we need to establish that the secondart trigger works.  If you're able to run with dual out and secondary trigger enabled its safe to assume so.

Assuming that the coils are wired like this:
Coil 1 to EC36-pin35
Coil 2 to EC36-pin33
Coil 3 to EC36-pin34
Coil 4 to EC36-pin36
Coil 5 to EC36-pin11
Coil 6 to EC36-pin12
Coil 7 to EC36-pin24
Coil 8 to EC36-pin10

With a firing order of: 1-5-4-8-6-3-7-2 give a firing order of:
0 - EC36-pin33
1 - EC36-pin24
2 - EC36-pin34
3 - EC36-pin12
4 - EC36-pin10
5 - EC36-pin36
6 - EC36-pin11
7 - EC36-pin35

[smurfinator]

phooey, that didn't work.  It coughs a bit but then floods and does nothing.  How can I check if the cam trigger is working?  I have double checked all wiring.


I tried enabling cam sync with dual fire and the car won't start so I assume there is something awry.  I have never been able to find info in the wiki on this subject in any depth, so I'm a bit in the dark.

I'm using Andy Mills cam sync settings (ABZ esprit), but he may have other settings which conflict (?).  Can't say as he has not replied to my latest email yet.

How do I relate my cam sync settings to the static timing from my 60-2 wheel?


Here are my other ignition settings...




Thanks!

[rob@vems.co.uk]

Are you getting an RPM reading when its cranking?

Try disconnecting the second sensor to see if the RPM stops reading.

[hilly]

I'll try and get my settings to you tonight as I have left my laptop at home.

I am however running V1.0.53, but I guess that shouldn't be a problem except for the h[2] format.

Hilly

[rob@vems.co.uk]

No the h[2] format is 1.0.73 on, theres a lot of cars running fine on 1.0.53

It should work with dual out and cam sync.

If you are terminal savvy you can see your wheel count with
Manmlp02 and mll a few times, theres some glyphs there which will count up, post what you see and I'll dig out more info.

Part of the reason that theres not much human readable information about the secondary trigger is that aside from the Nissan's I've never needed to use it, I've never had a problem with getting a car to idle and give good results on anything other than wasted spark and sequential injection using only the missing tooth.
The trick to sequential injection is to fire the injector at its cylinder's TDC, without the cam sync you will never know which stroke the cylinder will be on, but at TDC it will be either on its ignition stroke or its exhaust stroke, either of which give you a closed hot valve to inject the fuel onto.

[hilly]

OK, here is the spark order I am using on my ABZ



cylinder 1 = EC36 pin 35
cylinder 2 = EC36 pin 10
cylinder 3 = EC36 pin 12
cylinder 4 = EC36 pin 34
cylinder 5 = EC36 pin 33
cylinder 6 = EC36 pin 11
cylinder 7 = EC36 pin 24
cylinder 8 = EC36 pin 36

This gives the required firing order of  1-5-4-8-6-3-7-2

Now this looks completely wrong as it goes h[2]0 - h[2]7 - h[2]6 - h[2]5 - h[2]4 - h[2]3 - h[2]2 - h[2]1 which kinda doesn't make any sense what so ever (it didn't to me when I first started typing it out and I had to scratch my head a bit to figure it out again) until you understand how the cam sync works.

The h[2] numbers are counted backward, ie 76543210, easy so far, what the cam sync input does is as soon as it sees a trigger it resets the h[2] counter back to zero and then continues counting backwards, it is that simple. As the trigger tooth on the ABZ cam sensor is right before cylinder 1 TDC the h[2] counter is at 0 when cylinder 1 needs to fire, hence the odd order.
For any other engine with a sensible cam sync it would be totally different.

It is defo right as it runs perfect on my ABZ.
It took me a ages to get this right as it is so odd-ball, luckily I had the VEMS running on a bench with a crank trigger/cam wheel simulator and oscilloscope (see my blog) to get the order right before trying to get it running on the engine.
If you try to use a sensible h[2] order it won't work.

Hope I have explained this right, if not let me know and I'll have another go.

Hilly

[rob@vems.co.uk]

Nice one.  So it looked like the cam sync was the bad boy there then?

FWIW we have a signal generator program that generates wav files that allow you to test your setup using your PC/Laptop's sound card.  It works well with the VEMS test light (2x8 LEDs) connected to an EC36 connector.

[hilly]

Cam sync details are pretty light on the Wiki (in fact I hate it as searching for info is such a pain) as most go for wasted spark, so it took me a while to get the spark outputs right.

The cam trigger on the ABZ is a complicated multi tooth affair to allow it to get sync within one 1 rev. I just cut off all but 1 tooth to allow VEMS to be able to decode it.
I was then stuck with the tooth position, which was fine once I got my head around the h[2] order.

I used a PIC micro for the simulator as I could make it do a bunch of other stuff as well as test the triggers (such as testing the tacho output accuracy etc), but I'll have to have a look at the soundcard jobbie, could be useful.

Hilly

[rob@vems.co.uk]

Yep, cam sync details are light on the Wiki, but we're getting information here, which hopefully people will find useful.

[smurfinator]

Right, I suspected with our oddly modified cam trigger bells, we'd be in uncharted territory.  Where would we be without you boffins and your 'scopes 

Will report - thanks again, Andy and Rob for the extra time and effort.

Ben

...now, enough of this technical rubbish - I WANT TWIN TURBOS AND 1000 HORSEPOWER!
Can I just upload some new firmware and have the turbos appear?

[smurfinator]

well, drat there was some popping and backfiring but no running.  I think I really need your whole .msq file to see how my main trigger relates to yours.  Something is not quite kosher...


Ben

[rob@vems.co.uk]

Use configs and tables downloaded using the download-config.bat file, its the only way to be 100% sure.

Then I can generate the config and tables and run it on my test setup here.

While you're waiting are you still running on dual out?

Have you tried disconnecting all coils and pulling the plugs out except for cylinder 1, then getting cylinder 1 to fire consistantly when cranking?  (Pull the fuel pump fuse or relay out). If you get this sorted add one cylinder at a time.

Rob