I used to have a huge exhaust leak which would leak right out of the manifold because the gasket on the turbo to manifold broke , the car got dyno'd like that and put down 183 whp 186 wtq , i fixed it about a week after and right after i fixed it i went and did a full throttle pull making sure everything was good and the car boosted 20psi Haha

 

when is the meet in san antonio? I might attend if I know in advance

 

I am confused on your statment here bro. 16-20 counts of knock your ecu would seriously retard your timing most likely making you slow no matter what... unless you did like I did and adjusted your knock setting thereby "filtering" out alot of what I feel is false knock and thereby stopping the ecu from trying to compensate by retarding the timing. Even with my knock settings the way they are I can feel a noticable drop in power during a pull if I see my engine light do a fast flash and I know I am not getting more than 7 counts on the extreme end. Just trying to pick your brain maybe it can give a better understanding of how the pros do it.

 

The ECU would not retard the timing if both maps were the same, Im running my low and high octane maps both the same i get 1 count max every now and then WOT with timing at 7* advanced. Prob not the safe way but if im only getting 1 count every now and then, it doesnt seem to be very harmful

 

The way I understood it was that the ECU pulls 1* of timing from the high octane map for every 3 counts of knock AND sustained knock will decrease the "octane level", which will also cause the car to interpolate the low and high octane maps together. The lower the Octane number goes, the more it would pull from the low octane map. I think the car still pulls timing in severe knock situations regarless.

Side note, the Evo MAF was with me on my drive last night and to work this morning. EGT's are about 500 degrees hotter, which makes me think that my timing is a bit too retarded in the cruising area. I did my best to guesstimate what the proper loads were after short, "known" drives, but apparently I'm still a little off. Also, the car idles good cold, sits at 14.7, but when the car warms up, it starts to try and idle rich, like 11 or so. I can tell the ECU is using the o2 sensor to try and even it out to 14.7, but it just doesn't really sit there nicely.

So, my thoughts are this. First, the MAF adjusted a lot of fuel related settings, so I basically have to retune. The problem is I've never heard of anyone explaining how to set timing on an engine in the low load areas. Everyone says "Tune for WOT", but what do you do if you have an engine with a totally new computer that doesn't read air the same as it did stock.....then how do you set the timing map on that car???? Do you turn the knock thresholds off, and then go drive up hills at low load/rpm and increase timing until you see knock? I mean, should you ever see knock at those low loads? If you increase timing, will it mean better driveability/mpg? I would assume it would, but I don't know how those sorts of timing decisions should be made, I mean I understand no knock at WOT, but advance as much as you can...that makes sense. For now, I've just got "as close to stock" as I can in the 0-70 load area, which as of the Evo MAF turned into about 30-110.

Also, I guess it wouldn't hurt to pull the battery cable and let the ECU relearn once, would it? I think that might be part of my idle issue, either that the car is trying to relearn now, or it's not letting itself relearn......or my timing at idle is off, perhaps. I have it basically where my stock and last ROM were, but it's also the same as the stock lancer I logged.

 

Oh yes, i forgot about the ECU pulling timing in anything usually over 3 counts i think it pulls 1 degree of timing, however there have been times where i have noticed i get 1 count of knock and it pulls timing 1 degree as well, so i guess its whatever the ECU wants lol. As far as the MAF goes, i dont think you would need to re-tune the crusing areas timing, are you getting crazy knock or something? the only thing that i would see that would need re-tuning would be the fuel maps right? Any yeah you could try to un-hook the battery and let it re-learn a bit see if that helps.

I think that increesed timing in crusing mode will give a better more effective burn, thus reducing emissions and increasing MPG and better drivability. I have my crusing timing at about 34* or so with no knock problems, but when i had it to 38* i started seeing knock when i started to accel more, it was just too much timing i guess. But along with the increased timing in cruise and the increased AFR of 15.2 has given me a better MPG for sure

 

Yes it does not matter if you have your High and low octane maps set the same. As Hornstar stated the ecu basically has two ways of dropping timing to reduce knock. The first line of defense is the ecu manually retarding timing approx 1 degree for every 3 counts of knock it sees. The second line is when retarding the timing is not enough and the ecu is seeing prolonged counts of knock (usually above 6 counts) in which case it starts the interpolation procedure using more and more of the low octane numbers until it has successfully removed the knock.

Hornstar have you dont any WOT pulls yet? I am curious what your max load is falling at now. Have you tried interpolating any of my timing from my map into yours to see if anything changes?

 

mine seems to drop off around 204 and starts to decrease as rpms goes up and thats around 4500-4700 rpm which is pretty much my power band.

I might try to increase timing because im pushing around 12-13 psi right now. and add more more fuel to get to that 11.5 mark.

 

I got some WOT in right before I swapped to the 399 MAF, now I'm too scared to go WOT. Before the swap though, I was seeing load up to 160 when the pedal was "to the metal". I calced HP and torq with VDR and virtual dyno, about 150hp at a max of 8psi, but it was containing to climb and I only went to 5300 rpm. There was no knock on that set of pulls at all, but I never increased timing either. I guess that last comment sort of answers your question, I haven't yet increased timing for power...just tried to get it as close to what i was using on the lancer ROM.

Side note, I may get rid of the 399 MAF, the car was running perfect without it, and now that it's in....I can't get the car to idle at 14.7, it goes to 14.7 when i initially take my foot of the gas, and put it in neutral....but then it walks all the way over to 10AFR. Also, as I said, my honecomb was removed from the MAF, so it's possible that has something to do with it....though I don't entirely think it does, because the care is perfect everywhere except idle. Also, the sensor reads 25 at idle, it's not off or anything. I'm using the 399 MAF settings from the evo, but have tried the 482 and 501 scaling/compensation numbers. Thoughts anyone? I saw JRR had the same issue way back when, but the thread sorta just died out without a definitive answer.

Oh, I just unplugged my battery for 3 mins then put it back, and I'm gonna drive for 2 days with it using stock evo settings, and see if it works out any better. It's totally drivable, just sits too rich at idle.

 

The honeycomb is in the MAF sensor to smooth airflow, if you remove it i think it does indeed effect the readings to the ECU and could mess with the sensor, i would get a 399 MAF sensor with the honeycomb inplace and see if the readings are still off. Thats weird that you mention 25HZ at idle, mine is the exact same... hmmm..

 

I'd post the conversation I had with the guy selling it, but I'm sure it would cause problems. Basically though, it went like:

Hi, can I buy your MAF
Sure
Is it in good working order, nothing broken?
Yes, it's perfect
OK, I'll send 47 dollars your way
OK, it'll ship out tomorrow

2 weeks later:
So, did you get a tracking number or anything?
I lost it somewhere, it should be there tomorrow though

3 weeks later:
MAF shows up, covered in glitter (came out of a strippers car I think) and the honeycomb is ripped out

So, I thought you said it was in good working order, but the honeycomb part is broken.
No, it works fine, I took that out and made 550hp
OK, but I think that classifies as something "broken"
It works without it dude, besides what did you expect for 40 bucks, you can't find them that cheap anywhere.
Insert link here to other mafs for sale for 40 dollars
Here's a few, they have the honeycomb, and even if it were some sort of bad *** deal, be upfront about the part, don't keep something like that a secret.
Whatever dude, have a nice day....

Fast forward to me having idle issues, I think it may be, as 03lances has said in the past, something the computer needs to relearn. I drove the wife up to the corner store since she was having a craving for sugar, and it idled much better....not perfect, but a crap ton better. We'll give it another day or 3, and see how the old girl does.

Damn, I didn't mean for that story to go on so long!

 

Haha its all good bro. That kid deff should have told you that the sensor was "modified withought the honeycomb" or something, that was pretty messed up. And i know people who make around 500+ WHP with the stock evo MAF with the honeycomb, people LEAVE IT IN! Im pretty sure it gives it that "smoothing and more accurate reading to the ecu". If it didnt have a purpose it wouldnt be there! Glad its getting better tho!

 

From my understanding ppl with bigger turbos will sometimes pull out the honeycomb cause their afraid to suck it into the turbo. I too had an issue with my 399 when I got it. Pretty sure I posted pics in my thread of the "perfect" maf with the honeycomb smashed in. It actually did look like it was starting to get sucked in looking at the pattern. Regardless dude gave me the same bs how it still works perfect blah blah blah. If its not in perfect shape don't specify it is in your ad that's all I'm saying.

 

Yeah, I know some vette guys and they yank that thing out the minute they get the car and never have problems. I read a few evo threads where they almost suck them into the engine...but, like you guys said, probably ought to say "improved MAF, with honeycomb restriction removed" or something light that.

 

After the MAF swap, my low and mid fuel trims are -6.5 and -12.3, also...as I idle the stft or 02 feedback will slowly drop until it hits -25

Should I rescale my injectors? or try to work the issues out with the MAF scaling? Mind you I still have a little more driving to do before I make any adjustments, with the hopes that the ECU will eventually determine what's best for it....but with a mid of -12.3, it probably won't....it can't go much higher than that I don't think.

Side note, with the old maf, when I was idling, my logs typically show a long string of 0 in the O2 feedback at idle. My fuel trims with the old maf were -6 low and -2 mid, give or take 1 either direction....never -12.3