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Hay all. I'm new to logging and I'm a bit confused with the logs I have made from driving around.
First off here is the log I'll be referring to during this topic: I maybe jumping in the deep end here but one thing that has been bugging me is at 5:54 my spark starts to increase and my milligrams / cylinder
starts to go down. This is all going on while I'm still on the gas. I also noticed that there is some knock there as well and I was thinking if the milligrams / cylinder goes down while rpm goes up (according to the spark table) wouldn't it increase the spark advance, in-turn promoting knock because milligrams / cylinder should really be going up. Basically I would like to analyse this log on the forum and hopefully get some insight into how everything
works.

Added note I'm using VX Engine and trans TP5 V104 yoda69 edition as the adx.

I havnt got time to check the log at the moment, but as a quick answer, once the engine is past the point of delivering peak torque it'll still breath more air with more rpm, but overall it'll be less air per cylinder cycle. On a MAP VE table you can see the VE % (more or less the engine pumping efficiency) rise to its max point and then start backing off again even as RPM increases. As for the spark, I need to look at the log but i'd assume the factory spark map is optimal. That is even with less air in the cylinder, at that RPM it must need more advance.

Thanks for the replay, yep so even though the rpm is going up the efficiency of the engine is going back down. I think I understand that now. Still looking forward to what you have to say about the log.

that makes sense because the less air flow and more revs the more timing from my memory of MAF spark tables. so if it continued diagonally across the spark table as it would from idle revs increase and so does air so the roughly goes diagonally across the table, but as air flow starts to decrease it would keep going up the table but not across to the right but more to straight up or even to the left .....

have a look in the spark table and cross reference the load points in the table with the logs and see if the numbers match up at all.

I think the thing that through me off was as its starts to advance timing there is a point when the engine knocks,
it pulls the timing to 0 for about 1 to 2 tenths of a second but when the normal timing resumes the milligrams / cylinder is even higher.
Not sure whats going on here.

Also after looking back over the log I would say my car is making peak torque at around 4200 rpm. Would I be right in saying that?

I think TP might have had a little bit of a hiccup. The spark wont drop off the screen like its done. Try logging using just the 'engine data only' macro. Might need to change the macro slightly and use the 'small listen for silence' command else it will log a little slow.

Techoboy wrote:Also after looking back over the log I would say my car is making peak torque at around 4200 rpm. Would I be right in saying that?

Yeah i'd say thats about right, i just had a look at the ecotec tune i made when i had mine running on a 808 computer with map sensor and the highest WOT point in the ve table is 4000rpm and then drops off above that.

VL400 wrote:I think TP might have had a little bit of a hiccup. The spark wont drop off the screen like its done. Try logging using just the 'engine data only' macro. Might need to change the macro slightly and use the 'small listen for silence' command else it will log a little slow.

I'll look into using the engine data only macro I'll do another run later and re post if I have anymore questions.