Quote:
Originally Posted by ever_green
Now that the throttle has been tuned to perfection, I have moved on to other things like tuning fuel and timing. I have already increased part throttle timing without issues and now have been looking at idle timing. I was wondering what effects ignition timing has at idle and coasting on fuel economy? I have read lower timing during fuel-cutoff/coasting means less engine breaking. If so this is a good thing for fuel economy purposes? My current timing is set at 15* at idle and up to 30* when coasting at speed. For some reason the manual (5-speed) ECU calls for only 9* of timing at low RPM idle. Why the difference?
Idle Ignition Timing Table
as for fuel I have not been able to induce lean burn. Lowering values above 0 simply just sends the car to open loop. However I have managed to replace it with leaner numbers. This is how the fuel map looks like:
closed loop fueling table. To calculate AFR subtract from 14.7. Ie. -0.1 means 14.6:1 AFR. I simply replaced all values at lower RPMs with 0 to run at 14.7. |
It been long time since i messed around with timing curves .
things to watch out for If my memory is still good . high timing in low rpm/load can increase emissions . whats in your chart doesn't seem to bad at low speeds (500-1500 ).
What was the stock values .
Manual model will have no load at idle vers auto is always in gear so can handle slightly more timing , I think the curves are mainly influenced by emission output then performance .