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actual ignition timing

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hey guys

After some ideas and input on how to log actual ignition timing whilst on the dyno or if there are any product which can assist with this.

My current idea is to some how utilize an inductive clamp to display ignition advance via the ecu which they can be logged etc if possible. I want try and make some thing that can be easily used between different cars if I can.

if still got a bit of research to do to the theory side of things, but any one has done this your input would be appreciated.

From a reverse-engineering point of view this could make sense if factory maps are unaccessible. If, however, you consider the amount of time, money and effort it takes to elaborate such a (factory or another tuners work) map, you will most likely find that it is worthwhile to do the work yourself if standalone, or buy a cal file from a reputable tuner (less than second best).

I'm assuming you are looking to reverse engineer a factory ignition map or something of that nature? The simplest and most fool proof method would be to scan the data you want via OBD2. I'm not sure an inductive clamp is going to be much help as it will let you know when the spark has occurred but would still need to be synchronised somehow to TDC and this is probably much more difficult.

Is there any reason you can't use an OBD2 scanner?

No guys I have no intentions of tampering with a factory ecu. Its for a standalone ecu's, as the ecu I have doesn't log actual advance only calculated. But over the past few months I have seen alot of talk of these ecu's on social media from reputable tuners and racers of report of ignition timing wandering from what its mapped to. I wish not to go in too much detail as I dont want end up in legal court case.

But my ecu is only 2 years old so I cant really justify or afford to go out and buy new one, so Im trying find and accurate way of ensuring I know what the timing is actually doing. I think if I have a recorded data log of this if it is actually occurring, then I can take it to the manufacture and try and work out a solution or Ill be happy to know that my ignition timing is spot on and my engine is not at risk.

It isn't uncommon when reflashing an OEM ECU to have trouble with the ignition timing following what you expect as often the ECU may end up referencing several different tables to end up with the final ignition advance. Some of these tables or compensations may not initially be obvious until you dig a little deeper.

While you are using an aftermarket system, it's probably worth checking that you haven't got something similar going on with one of your trim tables or overlay tables effecting the actual vs expected ignition advance.

Being able to log what is happening outside of what the ECU is showing as commanded ignition advance gets a little tricky. While I'm sure that someone with the right amount of electronic knowledge could setup a logged event based off an inductive clamp on an ignition lead, timing all of this and then referencing it to TDC as well as commanded ignition advance would be challenging.

If the problem you are experiencing is repeatable under controlled conditions I would try putting a dial back timing light on the engine and physically watch what the timing does during a run on the dyno. You can then compare this to what the ECU reports as the supposed ignition advance. This can be a little difficult if you have anything resembling a normal ignition curve relative to rpm, but you could even hold the engine in steady state at a fixed rpm and watch the actual timing vs the reported.