After a bit of searching on active martix and here I'm coming up somewhat short on results if the timing table in our Ecu's litterally translates into degree's of timing.

So far I've found this:

- Its a target timing *eop* (so it "tries" to get there... i'd like to know a little more)
- Timing here is measured in a 8bit format converted to 10bit at the ecu


I ask this becuase supposedly the best leverage, most power, on our engines is something like 15 degrees ATDC which honestly seems no where near any of the values said on ecuflash. This makes me generally confused and i guess i have much learning to do to optimize power output of the engine.

I would appreciate links of any sort where engine timing optimization can be found, still searching this on my own.

 

The values you see in ECUFlash is not the point where the peak pressure occurs, where something like 15* ATDC would be optimum. The values that you see are the amount BTDC that the spark is fired. It take time for the flame front to propogate and for the pressue to peak.

So, don't confuse the timing tables with where you want your peak pressure to occur. The peak pressure point, in degrees ATDC, will change dramatically based on various factors, including octane of the fuel, RPM, boost, etc. That's why for the most part, you have to tune to find this point for your car and all of the variables that you are tuning with.


Eric

 

For me at 11:1 AFR on 93 octane, 16* of timing at 22psi seemed just about right before knock would start to show. A lower load allows you to get away with more timing and thats why we sometimes see 40* at cruise. Evos really dont need much timing as they are quite efficient even in stock form.

On race gas and now alchy I see my best results with 20* of timing. I could throw more at it without seeing knock but I didn't really see any returns from the added timing. I prefer to have a nice strong "all condition" tune rather than a bleeding edge weather specific tune.

 

Thanks I noted later after writing this post that in the myths on ignition timing as seend here:

http://www.innovatemotorsports.com/resources/myths.php

Typical timing is 22* BTDC, the goal of this bit of research is to ascertain the best methodology in which to tune for optimum power. I have to wonder if there is a geometrical way to find what would be "optimum" values in degree's for timing.

I could just up the timing to a point just before knock happens and leave it there but without knowing what point the peak pressure in degrees is happening it would be very diffulcult minus lots of dyno time to get the "best" tune.