Something I have wondered about for awhile.

A lot of todays tuners can give you the value of the Volumetric Efficency of the engine as it is running. Examples are TTS Mastertuner, SEST, and I think PC-V and Thundermax, and more I guess.
They get these values using the O2 sensors as these things feed back to the ECM to give the desired AFR.

Now The Question.

Why couldn't the, "Spark Retart System", which is computer controlled and kind of a feed back system, be used to reconfigure the timing tables to give best Spark???

Seems to me the necessary Data is there in real time just like the O2 Data.

Move the timing up or down in small amounts till just right, then maybe a 1-2% cut back and timing is perfect.

Just musing about.

 

It could be done.

 

Sure save a lot of---Interporlation Time.

 

It definately shows you when the knock retard is kicking in or not (signals you to do some adjusting).

 

I've been pushing my timing map ahead a few degrees at a time, doing data runs, and either dropping a degree of timing or adding fuel or both in the areas where knock is detected. Once a cell is at 45 degrees I don't push that one any further.

 

Thats the thing.
I love to ride but a "Data" run is tedious and not much fun. After awhile.
I guess ,"They", are holding that in their pockets for later.

 

I've red that "they" think VE calibration and timing calibration is like comparing apples and oranges. Apparently a simple or practical way to get timing right is not currently available. I hear advancing the timing to the point of knocking is the amateur thing to do, but not necessary the right thing.

I don't think "they" are holding back unless its a liability thing... not wanting the motor to go pop.

 

The spark retard system(ion sensing) can only sense when there is a problem(pinging) and pull timing as a precaution. It can't sense without what timing is good for the motor though. Advancing til you hear a ping is old school and doenst alway make the best power. Better mileage and power can be had with less timing in some areas as well. Equipment to accurately tune the timing can cost 10 of thousands.

 

Well said.

Dyno with a break can recreate riding conditions, as well as measure the power for comparison. Measure your AFR as well.

 

"They" can make the software so this... with only one little bity issue... The spark adjustment can only go one way. Down. Although it is a neat idea and one that has been asked of TTS for some time now there is just no real way of using the system to create a good spark table for your bike.

As stated above, the best way is on a dyno and tune your spark curve live via the power band observations. This takes a lot of time and experience to do right.