Hondata

Are these numbers, below atmospheric pressure, actual HONDA timing values? Or have they been slightly modified by Hondata?

Anyone?

The numbers are from a P72 ECU, but the ECU will add timing with increasing rpm depending on engine temperature & knock. It's like a fuel table - you cannot express a fuel table in injector duration but the actual duration depends on environment conditions.

So for example, 982mBar @ 7500RPM the timing tables shows 29.75. This does NOT mean a total of 29.75 degrees advanced past TDC?

Is this 29.75 degrees past TDC plus OR minus whatever the ECU decides dynamically? If this is correct, is there any way to find true ignition advance?? Thanks.

Sounds like you are so confused.

Unless there is engine knock and heat related problems, the timing you will read is exactly the same like what is on the map.

But you need to synchronize your Datalogger with the ECU first. There is a procedure in the manual. Take note that the maps are reading four sites at a time so it extrapolates a final value for actual timing. like at idle where the timing is the sam on almost 4 map sites then the actual timing will read what is in there.

It is timing advance so the numbers are is degrees before top dead center.

Thanks for the reply Quicksliver, but I am far from confused...maybe just not clear. I do understand synching up the timing.....

Hondata states:

depending on engine temperature & knock.

So I suppose I have an answer to my question before I asked -- No, the numbers listed in the timing map are not absolute static values. (not under all circumstances)

I assume 'depending on engine temperature' means it dynamically adjusts the timing +or- the static value depending on the engine temperature....and the hotter it gets, it may pull more etc..

Quicksilver you said in a knock or heat related 'problem'...

Are you suggesting that Hondata is saying those timing values are 100% static unless you are overheating? That is the only heat problem I'm aware of.

If my above assumption is correct, I'm simply wondering if there is any way to see what the ECU does to the timing depending on those factors.

is the map up top the actual numbers that are used by honda in a stock GSR? what year? I have a stage 2 that I have not tuned yet, but I am trying to gain some knowledge beforehand. Thanks.