Does anyone usually use the "accel enrichment" table?
Does anyone usually use the "accel enrichment" table?
I've noticed the table there before but I've never used it, instead I would just keep tuning to my 3rd and 4th gear logs. Well, due to an unfortunate circumstance the person I used to car pool into work with is being transfered to a different shift and I now need to drive my car on a daily basis. No biggie, I love to drive it...except for one thing I noticed yesterday coming home. I was in 5th gear around 3100 rpm cruising down the highway, and someone flew up behind me. So I stepped hard on the gas to move up and out of his way, and I looked at my lc-1 as I did and saw 12.5afr at almost 20psi. I've been at this long enough to know that's way too lean, especially for 5th gear. So that being said, how does this "accel enrichment" table work, and how should I adjust it to reach a much safer (like a low 11's) AFR for when I'm in 5th gear?
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I'm not sure anyone properly understands this table. There are some other tables that are unpublished that look like they are more relevant to acceleration enrichment. The greatest need for acceleration enrichment is I believe in the area of normally aspirated response - a quick richening to make the initial throttle movement crisp, not to still be there by the time the turbo has spooled up to full boost.
So, I think acceleration enrichment is not what you need here. You need this area of the fuel map richened disproportionately to say the 4000-6000 RPM area to get the same wideband AFR I find. For example, I have 9.8 in my fuel map at 3000 RPM and 240 load to get mid-high 11s wideband AFR at this point, whereas I have 10.2-10.7 in my fuel map from mid-high RPM to keep wideband AFR in the mid 11s all the way up.
So, I think acceleration enrichment is not what you need here. You need this area of the fuel map richened disproportionately to say the 4000-6000 RPM area to get the same wideband AFR I find. For example, I have 9.8 in my fuel map at 3000 RPM and 240 load to get mid-high 11s wideband AFR at this point, whereas I have 10.2-10.7 in my fuel map from mid-high RPM to keep wideband AFR in the mid 11s all the way up.
i have a map from an evo i was tuning that has only the accel enrichment tuned on the map. He got the car used, and the guy before him said that it was a mail-a-flash or one of the e-flashes sold on this site... i cant remember the name.
but it was a POS tune, it kept the stock fuel table, and ran absurdly rich at part throttle (9.9:1), and lean (12.5:1) at WOT.
that, and the ignition was all block tuned.
when i put that map on my car, i was only able to hit 200-205 load ranges, tapering to just over 190, and it was running 18° of timing at redline with the AFR at 12.3-12.5:1
my own tune is able to hit 250-260 load and hold over 210 load till redline... thats with 14-16° of timing at redline and 11.8:1 afr
dunno which one is faster, or makes more power, but it was interesting to see a completely untouched fuel map, and only the enrichment map touched.
but it was a POS tune, it kept the stock fuel table, and ran absurdly rich at part throttle (9.9:1), and lean (12.5:1) at WOT.
that, and the ignition was all block tuned.
when i put that map on my car, i was only able to hit 200-205 load ranges, tapering to just over 190, and it was running 18° of timing at redline with the AFR at 12.3-12.5:1
my own tune is able to hit 250-260 load and hold over 210 load till redline... thats with 14-16° of timing at redline and 11.8:1 afr
dunno which one is faster, or makes more power, but it was interesting to see a completely untouched fuel map, and only the enrichment map touched.
in general, accel enrichment is only a momentary thing. I havent watched it much on my evo, but on my old DSM it was only doing something as you were moving the throttle pedal, and goes away once you reach relatively no movement. That table takes the place of the old accelerator pump, which just gives an extra bump of fuel for throttle tip-in.
"The Bro" is the only tuner I've witnessed modifying the Accel Enrichment map. In this specific cast it was completely maxed out and the fuel map had LOTS of values in the 7s.
Do you still have lean spool enabled? I witnessed odd AFR shifts in higher gears when it's left enabled ... but it's usually the opposite of what you've described.
Do you still have lean spool enabled? I witnessed odd AFR shifts in higher gears when it's left enabled ... but it's usually the opposite of what you've described.
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Stock Turbo= No need to adjust it
Bigger Turbo= Yes since the moment of enrichment will be moved to where the new turbo spools up.
Bigger Turbo= Yes since the moment of enrichment will be moved to where the new turbo spools up.
Last edited by Ph3n1x; Jan 4, 2008 at 04:07 PM.
"The Bro" is the only tuner I've witnessed modifying the Accel Enrichment map. In this specific cast it was completely maxed out and the fuel map had LOTS of values in the 7s.
Do you still have lean spool enabled? I witnessed odd AFR shifts in higher gears when it's left enabled ... but it's usually the opposite of what you've described.
Do you still have lean spool enabled? I witnessed odd AFR shifts in higher gears when it's left enabled ... but it's usually the opposite of what you've described.
I have no idea what AE does but I have done a test on it with positive changes in the AFR graph. The AFR pattern is the same when overlayed to AE with higher values but the lower value graph comes on earlier. They overlay perfectly, just change time
Can you explain this a little better? Sorry, I quit smoking this weekend so I'm a little retarded today lol. If you have any graphs or logs that show what you're talking about, that would help even more.
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