I have noticed the evo seems pretty prone to knock, arund 2800-3200 in the 10-30.. THis only really happens in 4th gear-5th gear.. When punching if from 2k-2500 it will knock everytime right in between that range depending on when boost hits.. This was happening with the txs base map, so i made som changes to my low end and got rid of most of it.. Still in 5th it will want to knock..

Has anyone else had this problem? I have noticed it on my friends car and my own car..

D-

 

I've seen it when I am doing WOT runs. What A/F's are you running in that range ?

I was having trouble with the stock map right off the bat - they were way too lean on my car and I had to richen up substantially throughtout the rev range and retard timing. After going through this exercise I believe I got rid of the low rpm knock though.

Also one other thing to consider - pulling from 2k to 2.5k rpm in 4th or 5th gear takes abosultely forever ( the turbo is out of boost etc ) so in all probability you won't actually drive like that in real life. You'd probably shift down a gear or two to get that turbo spooling.

 

5th gear i get knock above 3500 i gotta look into that when i get my tuner in the car saturday to see what my afr's are.. I am running the fuel map i made for my friends car, and the base txs stg 2 timing map with some timing yanked in the low end..

My friends car i made the map on was running 12.5:1 in the lower rpms and load then tapers to target afr of 11.6.. I pulled a bunch of timing out in that area, from 10-40 load sites i am only running like 7-8 points there.. I really liked the utec for the wrx more since load was based on MAP not MAF, i need to get a map sensor..

 

Are you using the new open loop fueling feature? If you are try setting the MAF frequency for mapping low point to 6 (600hz) and set the crossover threshold in the open loop fueling to 35% it should allow the ECU to transition more smoothly and should eliminate the knock..

 

Oh, and using the MAP sensor for load reference does help, but my experience with it so far is the MAF Karmann frequency is a much more accurate indicator of engine load..

 

Jack, i am running open loop. I believe 6(600hz) is the default value, and my crossover is also at 35%(i believe that is default also)

The reason that i think having map based load would clear this up is because the maf is not seing enough air to get the load up in those rpm's, if it was map based when i hit 19-20 psi i would be at 100 load rather then 10-20%.. The low end is suffering from this, sicne you have to have timing so soft down there just for 4th and 5th gear hits.. If i had the map i could just tune the 70-100% 2-4k really soft and the only time i would hit those sites is on 4th and 5th hits..

I do not know enough about the Karmann.. I need to start reading up on it..

How much of a pain is it to mount and run, and configure the map? After my wrx which nothing on the car was stock i just want a car where i am not working on it ALL the time.lol

dave

 

Sounds good, but from my observations of the log readings of the MAP sensor, I'm wondering if it would really work that well. The reason I say this is that when logging in 3rd gear my MAP sensor is telling me I get peak boost at 3900 rpm ! But if I do a WOT run in 4th or 5th gear I get peak boost right on the money at 3500 rpm.

So from the results of my UTEC logs, if you based load on the MAP reading my UTEC would only think it is at the 70-100% load point when it hits 3900 rpm and would therefore run lean at 3500 rpm when it actually is pushing max boost.

Does anyone else with a MAP sensor see peak boost at 3900 rpm for 3rd gear but at 3500 for 4th and 5th gear ?

The more I think about this issue, the more I think this could also explain why AF ratios for 3rd gear runs are always 0.5 leaner than when in 4th or 5th - as for the boost, the A/F ratio is changing faster than the UTEC can log it and so the UTEC ends up averaging the reading high ???

 

What your describing is the reason why you tune in third gear, then go through the other gears and fit the load sites for them (generally different load results in slightly different load sites.

You won't see much of a difference.. However you can passthrough ECU timing at lower load sites and RPM's sort of cut a small "Triangle" out of the area you see issues in the 10 and 20% load sites.. then it should average the timing into the 30% load sites.. I've done that before to address a different issue.. But it does address a sudden timing/fueling change that would register as knock..