Alpha-N Questions
Posted: Sun Mar 01, 2009 10:10 am
First... what the heck does "Alpha-N" stand for, anyway?
Okay, so I started using Alpha-N below 2000 rpm to get better control of the idle on my engine because it has a VERY peaky MAP signal. Worked like a charm, allowed me to tune the low rpm areas for some civility for things like idling around in 2nd gear and such.
Yesterday, I finally decided to go full Alpha-N with it to see what it would do. I'm still in the early stages of tuning it, but so far it seems to be coming together nicely. I'm finding "midrange" that I didn't have before, which is nice.
On with the questions!
Wondering if the Alpha-N MAP translation is used for timing or if the timing advance is still based on "real" MAP? Could make for some interesting tuning of the timing map if Alpha-N is in the equation.
And I'm wondering if my logic is correct for how I've set up the Alpha-N TPS table. Here's what I did: I changed my MAP bins in the VE table to every 10 kPa from 10-120. If the Alpha-N interpolates the way I think it should, having the first 10% of TPS translate to 60kPa gives me 6 bins of resolution for just off-idle. (probably overkill, but what else am I gonna do at 1000 rpm???) Going up from there, I start focusing more on the mid range, ensuring that I always have a 1:1 relationship between TPS and kPa in the mid-throttle range. And, on the high-end, where I'll not really be using low throttle, I've expanded the high-throttle bins to give finer throttle control up there.
I know that not many people seem to be using Alpha-N, but if anyone can confirm that I'm headed in the right direction, it would be appreciated!
Okay, so I started using Alpha-N below 2000 rpm to get better control of the idle on my engine because it has a VERY peaky MAP signal. Worked like a charm, allowed me to tune the low rpm areas for some civility for things like idling around in 2nd gear and such.
Yesterday, I finally decided to go full Alpha-N with it to see what it would do. I'm still in the early stages of tuning it, but so far it seems to be coming together nicely. I'm finding "midrange" that I didn't have before, which is nice.
On with the questions!
Wondering if the Alpha-N MAP translation is used for timing or if the timing advance is still based on "real" MAP? Could make for some interesting tuning of the timing map if Alpha-N is in the equation.
And I'm wondering if my logic is correct for how I've set up the Alpha-N TPS table. Here's what I did: I changed my MAP bins in the VE table to every 10 kPa from 10-120. If the Alpha-N interpolates the way I think it should, having the first 10% of TPS translate to 60kPa gives me 6 bins of resolution for just off-idle. (probably overkill, but what else am I gonna do at 1000 rpm???) Going up from there, I start focusing more on the mid range, ensuring that I always have a 1:1 relationship between TPS and kPa in the mid-throttle range. And, on the high-end, where I'll not really be using low throttle, I've expanded the high-throttle bins to give finer throttle control up there.
I know that not many people seem to be using Alpha-N, but if anyone can confirm that I'm headed in the right direction, it would be appreciated!