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Discussion Starter #3
mods that make a difference: 8.5:1 compression, bc stage 3 cams, CNC port head, 50 trim, 900CC injectors. AEM 3.5bar, GM IAT sensor, return line on boost/vac source base pressure 43PSI.

O2 feedback sucks ass. It takes forever to get to its target. No matter what gets changed (its 100000000000 times better than the wizard right now...but no where near perfect)

Hot start problem that i've complained about since i've owned the EMS....let it sit for 10-20 min after driving around and then restart it, it runs lean (18-19:1 afr's for 10sec-2min) then settles itself out.

Warm-up enrichment afr's are different EVERY TIME. This confuses me. It could be the same temp outside, same IAT's, same everything and it'll be at 12:1 once and 14:1 the next.

Slowing to a stop, as soon as you're out of decel fuel cut, it runs 12:1 until you reach a complete stop....then it idles normal again. (even though it sits in the same cells as the idle)

might think of more later.
 

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Discussion Starter #4
it has a 13.5:1 idle without O2 feedback on, runs 14.5:1 to 15.0:1 through out the RPM and vacuum range till approx 5inhg then it runs 13.5 and progressivly richer up to an 11.2-11.5 under boost without O2 feedback on.

What makes you think thats too much fuel at low RPM's?

Will not idle leaner than 13.5:1
 

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mods that make a difference: 8.5:1 compression, bc stage 3 cams, CNC port head, 50 trim, 900CC injectors. AEM 3.5bar, GM IAT sensor, return line on boost/vac source base pressure 43PSI.
nice mod list:thumbsup:
O2 feedback sucks ass. It takes forever to get to its target. No matter what gets changed (its 100000000000 times better than the wizard right now...but no where near perfect)
yea you took out most of the gain on the o2 fb
Hot start problem that i've complained about since i've owned the EMS....let it sit for 10-20 min after driving around and then restart it, it runs lean (18-19:1 afr's for 10sec-2min) then settles itself out.
may be your o2 FB is delayed big time in the cold and you need enrichment we need a cold start logw/ the start screen parameters
Warm-up enrichment afr's are different EVERY TIME. This confuses me. It could be the same temp outside, same IAT's, same everything and it'll be at 12:1 once and 14:1 the next.
its based on the coolant temp
Slowing to a stop, as soon as you're out of decel fuel cut, it runs 12:1 until you reach a complete stop....then it idles normal again. (even though it sits in the same cells as the idle)
i would need to know what your lowest load is in psig and may again be tied to the o2 FB
might think of more later.
the map looks nice (100% boost comp) i think your idle % map needs to be finished, and your idle fuel and ign. FB needs to be toned down. and you dont like much timing above 15 psi do ya :jester: (I assume its a pretty big turbo)
i would lower your RAW values (mb/sec) to allow some head room :readclose





please post some logs with the aproprite parameters (you will need to .zip em)

all and all looks like a good start, and if its working like you say should just need some minor touches
 

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ok, lets start by selecting the aproprite O2 sensor in your sensor setup, then set the sensor gain, make the sensor and gauge read the same if its a eugo box dont wory about that last step. then go to the fuel<o2 feedback<o2 sensor wizard and select the correct sensor again (copy your FB map first so you can paste it back up). your FB cuts out at .91 psi so you have no load control, if it was me i would make a back up copy of this map (just incase) then set all the original settings from the 1510 base map in the O2 FB area and start tuning your FB again http://www.srtforums.com/forums/f298/o2-feed-back-534658/
 

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Discussion Starter #13
The reason there is no o2 sensor configured is because i changed all the settings. I'm running an Innovate wideband and the numbers are way way out when you compare the actual AFR to what the AEM sees. After dealing with AEM a bunch on this I was able to go in with the laptop and change the settings of both the LC-1 and the AEM so now they read the same. Because I changed the afr/volt table it unchecks the O2 sensor I have.

The base settings are way of. It ossilates way to much before it reaches the target O2. I've been playing with it but i really dont know what im doing when it comes to that.

Im still working on the boost fuel table so I turned O2 feedback off under boost.

I dont know whats going on with the idle very much. Tried a million things but still working on it. I only recently figured out how to get it to run off the maps. (TPS voltage thing)

I recently got rid of my AVC-r and am now using the EMS to control boost, so i'm tuning as I go. I havnt gone over 16PSI with the new tune (ran 24 before, but not full boost comp) So still working on the fuel/timing for anything over that.
 

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The reason there is no o2 sensor configured is because i changed all the settings. I'm running an Innovate wideband and the numbers are way way out when you compare the actual AFR to what the AEM sees. After dealing with AEM a bunch on this I was able to go in with the laptop and change the settings of both the LC-1 and the AEM so now they read the same. Because I changed the afr/volt table it unchecks the O2 sensor I have.

The base settings are way of. It ossilates way to much before it reaches the target O2. I've been playing with it but i really dont know what im doing when it comes to that.

Im still working on the boost fuel table so I turned O2 feedback off under boost.

I dont know whats going on with the idle very much. Tried a million things but still working on it. I only recently figured out how to get it to run off the maps. (TPS voltage thing)

I recently got rid of my AVC-r and am now using the EMS to control boost, so i'm tuning as I go. I havnt gone over 16PSI with the new tune (ran 24 before, but not full boost comp) So still working on the fuel/timing for anything over that.
if I was you I would set up that sensor and use the sensor gain to match it up. once its set up correctly I think you will be plesently suprised :thumbsup:


setup>o2 sensor>options
 

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One thing regarding your hot start issue. You may want to check out how quickly your wideband is sending a true AFR signal to the EMS for it to make corrections off of.

I know on my Zeitronix unit, it takes about 26 seconds to warm up (regardless of temps) before it starts sending a true AFR signal to the EMS. During the time that the sensor is warming up, it sends a false signal to the EMS that, in my case, would usually read rich in the EMS, and as such, the EMS would try to compensate for it with O2 feedback. This would cause the car to run horrible on hot starts.

To fix this, I set a static value of 26 seconds in the "Start Extra Decay Table", so that the EMS doesn't make any corrections off of the signal from the wideband until it is actually reading and sending a correct afr value.
 

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Discussion Starter #16
Thanks for all the input.

Nutz...Im going to try to do the gain thing tomorrow. I'll have to reset all values in both the EMS and the LC-1. How do you adjust the gain so that it reads the same?? How fast do I want the LC-1 to read the afr's? I slowed it down because it was VERY fast. The EMS couldnt keep up
 

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Discussion Starter #17
Why would you change the ms to 25? I had it at 30 for a while but let AEM pro rescale it and thats what they put it too.
 

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Why would you change the ms to 25? I had it at 30 for a while but let AEM pro rescale it and thats what they put it too.
your raw was almost toped out it max's at 255 you were at 233 :wah?!: that leaves less than .26ms of pw adjustment up top (you had NO head room at all)

IE: if you pass 18-20psi and you run lean there is no more fuel the computer can add, your boost comp is based off of raw (a max of 5.1ms pw 255*.02=5.1) so all your aditional tuning would need to be done in the boost fuel compensation map by % across the entire rpm range









 

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Discussion Starter #19
But is that not how a full boost comp map works? Do you not base your raw fuel off engine RPM and then use the boost comp map to add/subtract more/less fuel depending upon boost pressure or engine vacuum?

When i did the initial tuning I set up the boost comp table as from AEM forums (Boost Compensation tuning explained (again) MicroSecBit too!). Then I did multiple runs at wastegate boost pressure (using the AVC-r/EMS to spool the turbo as fast as possible) and then adjusted my afr's so that I had 11.5:1 throughout the entire RPM range, then I was using the boost comp map to add fuel for the increased boost pressure. Once i had that tuned, I used the Optimize fuel map feature (I think thats what its called) to get the highest possible raw number and then fine tuned the main fuel map from there.

Pretty much the formula that I found on AEM forums for tuning the boost comp.
 

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you can get the same pw with less raw, I like head room just incase (I never go over 200 on BC). raising the mb/sec value will lower the resalution a bit but thats not a real issue unless your under 30-40raw


raw value X mb/sec value (.00??) = pw....after thats calculated the computer multiplies it by boost fuel% and throttle fuel % and adds and subtracts for and other fuel modifiers to get a final PW


as it sits now you highest VE will only take a 10% change on the map then you will need to use the boost comp table but that adds across the entire RPM range for that load.

its your map I am just giving some feedback
 
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