weitek Posted July 14, 2009 Share Posted July 14, 2009 Good read Thanks Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 Nm see below. Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 Have you cleaned the MAF sensor lately? Link to comment Share on other sites More sharing options...
Spec B Posted July 14, 2009 Share Posted July 14, 2009 No; I pulled the maf about 6 weeks ago and it looked ok (no oil or grime that I could see) but I never actually cleaned the maf. Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 I'm just wondering because there is a pretty wide spread on your OL fueling. It's to the point where I wouldn't feel comfortable leaning it out any further until I really understand what it is doing. I'm thinking maybe the maf is dirty or maybe that particular intake has a lot of turbulence. I haven't tuned a Typhoon before.. only stock boxes with high flow filters and the APS 70mm. My other thought is perhaps the fmic is doing it.. but it's towards the mid and end of the pull so that doesn't really make sense unless there is a leak somewhere. Have you ever checked for boost leaks? Link to comment Share on other sites More sharing options...
Spec B Posted July 14, 2009 Share Posted July 14, 2009 From what I have read the Typhoon is one of the more stable intakes and prefered by tuners...but this is just stuff I read. I had never suspected a boost leak but I do frequently check all the vac lines, and IC pipe connections, I checked this weekend and they were fine. I could try cleaning the maf..that should be easy enough. What percentage is the scaling off by..using AB sheet I compared logged AFR to the map targets and above 3500 rpm I remember that it varied (on average) less than 1% from the map target...is that too much or am I reading the variances wrong? Link to comment Share on other sites More sharing options...
Spec B Posted July 14, 2009 Share Posted July 14, 2009 Here is a copy of my variance sheet based off one of the latest 3rd gear runs. AFR Variance.csv Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 The variance on one run is only part of the story. When I plot all your runs in a scatter it is all over the place. I've tuned several other cars with a wide band and never seen it that bad. Being lean or rich in spots is fine and I can work with that, but when it's both lean and rich in the same spot throughout 60% of the chart I start to scratch my head a bit. Here's a graph that combines all your WOT data in a scatter. Even if I ignore below 3 load it's still a mess. Your OL fuel map is flat after 3 load so it should NOT look like that. I'm not quite sure what to make of it. http://i305.photobucket.com/albums/nn215/weitek/olf.jpg Link to comment Share on other sites More sharing options...
Spec B Posted July 14, 2009 Share Posted July 14, 2009 Ahh..now I understand. I have always been looking at it from a single run persopective. I wll look for any leaks tonight..I am hoping a dirty maf is the culprit. i wonder if the WB02 may need calibration? Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 Ahh..now I understand. I have always been looking at it from a single run persopective. I wll look for any leaks tonight..I am hoping a dirty maf is the culprit. i wonder if the WB02 may need calibration? That's a good idea also (the wb02). I suggest using some MAF cleaner spray. You can pick up a can at most auto parts stores. I've heard it's also safe to use non-chlorinated brake cleaner but I prefer to use MAF specific spray as they are quite expensive if you have to replace one. Make sure you spray it up inside the MAF housing as much as possible - don't just clean the IAT probe. Give it a couple good bursts and let it sit for a few mins, then spray it again. Wait 5-10 mins before putting it back on the car. I also suggest doing an ecu reset afterwards. You can do that with Learning View or Rom Raider Logger. Actually I think I am going to post your new map so you can flash that when you clean/re-calibrate. I have been sitting on it since I wanted to fix the OL fueling a bit but at least you can benefit from the re-scaled MAF and the lower end OL changes I made. It should improve your spool and peak torque considerably. I'll post that in a minute. Link to comment Share on other sites More sharing options...
Spec B Posted July 14, 2009 Share Posted July 14, 2009 Thanks for the work on the map..I will try to pick up the cleaner tonight. Link to comment Share on other sites More sharing options...
snow05gtRI Posted July 14, 2009 Share Posted July 14, 2009 nice thread. its cool to see open tuning like this... Link to comment Share on other sites More sharing options...
weitek Posted July 14, 2009 Share Posted July 14, 2009 Thanks for the work on the map..I will try to pick up the cleaner tonight. Here's the new map. The fueling is much more aggressive during spool up but it should still be totally safe (as long as it works as intended). Please log carefully and work your way up to it. For example start in 2nd gear - floor it from 1600rpm or so and only let it boost to about 5psi. Log it and make sure the AFR looks okay and it isn't knocking. Then repeat but go up to 8-10 psi, working your way up to full boost. It should work fine the way it is but this will catch any potential problems before it might damage your engine. Repeat the process and test all the gears. When you feel like it's safe do some wot/shifting and try to mix it up to cover all the rpm's and load ranges. Try to make it knock to find the weak spots. And if you're ever not sure or think something is wrong just stop and come back for help. Good luck. http://www.subyshop.com/Spec B Rev 27.hex Revised base timing, open loop fueling, maf scaling and wastegate duty cycle. O yea, please be sure to reset the ecu after flashing this map. nice thread. its cool to see open tuning like this... Thanks. My hope is that I can help others and learn something in the process. Plus I have fun messing around with this stuff. Link to comment Share on other sites More sharing options...
weitek Posted July 15, 2009 Share Posted July 15, 2009 It's very common for FMIC'd Subarus to dip into the 10s when you hit the gas. There have been threads about it at Nasioc and RomRaider... when I saw my car doing it, I suspected tip-in, so I zeroed out tip-in and the problem was still there, so I'm certain that's not the cause. The prevailing theory so far is that there's a delay between when the MAF sees a rapid rise in airflow and when all that air actually makes it into the cylinders. Basically, it takes time to pressurize the FMIC and charge pipes, and during that time the MAF is reading more airflow than the cylinders are getting, so the mixture goes lean. I'm not convinced that's actually what causes it, but some people are. At some point I want to switch to blow-through MAF, to see if that really makes a difference. A second possible explanation is called Tau, or X-Tau, or "wall wetting." I've actually been meaning to bring this up on the RomRaider forums for a while now... http://www.megamanual.com/ms2/xtau.htm I have a couple ideas for investigating that possibility via creative logging, for example free-revving the engine just prior to the log pull to see if that blows out the fuel on the back of the valve / walls of the intake port. But even if the "tau" theory is correct, it still leaves the question of why the rich dip is more pronounced with FMICs, so I'm guessing there's still more to the story. I just read through the link, and I've been doing some research on the subject. I've got some ideas but no solid leads at this time. Am I to understand that there is currently no proven work-around for avoiding the rich spot on a fmic'd subie? Link to comment Share on other sites More sharing options...
NSFW Posted July 15, 2009 Share Posted July 15, 2009 None that I am aware of. I have heard that using a blow-through MAF will help, but I haven't seen before-and-after data to support that claim yet. I've only seen it discussed in relation to FMICs, but I also wonder how prevalent it is with TMICs too. People who look at one log at a time, and who always do logs from 2000 to redline at WOT, are not necessarily going to see it. It would be really easy to "fix" it with the fuel table, and then be correspondingly lean in the same cells when you're not doing a 2000-to-redline-at-WOT pull. I like to do a whole bunch of logs of various scenarios and then come home and look at scatter plots, so it jumped out at me right away. But in the forums people are pretty focused on 2000-to-redline WOT pulls, which can hide the problem. Link to comment Share on other sites More sharing options...
Spec B Posted July 15, 2009 Share Posted July 15, 2009 Okay...couple of things. Cleaned the Maf - reset and drove around with the rev 26 map (not the new one)...I was hitting higher voltage than yesterday, so I guess the maf was dirty. Something is up with my fuel trims at idle. I have been logging for about 8 months straight and my LV had never shown more than a 3% adjustment. I was hitting -9% before the maf cleaning and -10% after. I looked everywhere for a leak and cannot find one. I highly doubt this, but can the problem be caused by the tune? The problem immediately started after I flashed rev 26 on saturday (I even took a LV sat morning before I flashed rev 26 and the trims were less than 3%) but I also adjusted my intake right before flashing your map..so I don't know if the trims being off are a result of the map or my tinkering. I will continue to hunt it down.. So on to the good stuff..flashed the new version and started slowly stretching the logging runs. Car feels great! I think the maf cleaning is causing me to run a little rich on top, but it still felt strong. I did a few 3rd gear runs and use airboys sheet to see changes in 50-80 and 60-80 runs and it looks like it shaved a little time off over the last time. Here is one 2nd gear and two 3rd gear runs: romraiderlog_20090714_222416.csv romraiderlog_20090714_221621.csv romraiderlog_20090714_222146.csv Link to comment Share on other sites More sharing options...
Spec B Posted July 15, 2009 Share Posted July 15, 2009 And here is some mixed hard driving and highway cruising. Caught a few knock events on this log.. http://www.box.net/shared/okr9t7y6ks Thanks for all the work on the map, I really appreciate it! Link to comment Share on other sites More sharing options...
weitek Posted July 15, 2009 Share Posted July 15, 2009 It's possible that I changed something that caused the maf problem. I will check rev25 against rev27 to see if I can find anything. Link to comment Share on other sites More sharing options...
weitek Posted July 15, 2009 Share Posted July 15, 2009 Here is Rev 28: http://www.subyshop.com/Spec%20B%20Rev%2028.hex I restored the Rev 25 MAF scaling, load comp, etc - as well as Tip-in Enrichment settings. Revised IWGDC, Base Timing, Timing Advance and Open Loop Fueling. Link to comment Share on other sites More sharing options...
weitek Posted July 15, 2009 Share Posted July 15, 2009 I am experimenting with some new DBW mapping using linear tables. I got the idea from a beta map evasive posted on the RR forums. I will be testing it on my car tomorrow and if it works as well as I expect I'll include it in your and Franz's next update. http://www.subyshop.com/images/dbw.jpg Link to comment Share on other sites More sharing options...
NSFW Posted July 15, 2009 Share Posted July 15, 2009 I did the linear requested torque thing on my car, I like it much better than stock. On my car the stock table was requesting 50% torque at 20% pedal, so it was touchy down low and numb everywhere else. Link to comment Share on other sites More sharing options...
Spec B Posted July 15, 2009 Share Posted July 15, 2009 I read about those also...they look promising! I will flash the latest Rev tonight. One other thing to note..not sure if this is normal. When holding the accelerator in nuetral at 2500-2800 rpm I get some roughness (misfire) increments on all the cylinders. Maybe one or 2 increments then they return back to 0. This scared my a bit, since I did not know if it was normal. I started logging it while driving and I the roughness counts stayed at 0 both in cruise and WOT. I have never tripped a CEL regarding roughness and the car is running fine. Is this normal behavior? For the most part, it only happens in nuetral. It would be great of someone could quickly log roughness and hold the RPM at 2500 while in nuetral and see if they get similar results. I have 25K miles, no oil consumption and no other symptoms. Link to comment Share on other sites More sharing options...
rtbrjason Posted July 15, 2009 Share Posted July 15, 2009 I read about those also...they look promising! I will flash the latest Rev tonight. One other thing to note..not sure if this is normal. When holding the accelerator in nuetral at 2500-2800 rpm I get some roughness (misfire) increments on all the cylinders. Maybe one or 2 increments then they return back to 0. This scared my a bit, since I did not know if it was normal. I started logging it while driving and I the roughness counts stayed at 0 both in cruise and WOT. I have never tripped a CEL regarding roughness and the car is running fine. Is this normal behavior? For the most part, it only happens in nuetral. It would be great of someone could quickly log roughness and hold the RPM at 2500 while in nuetral and see if they get similar results. I have 25K miles, no oil consumption and no other symptoms. I see 1 or 2 counts that quickly return to 0 under those same conditions. Just while revving lightly in neutral or holding the rpms to 2500-3k. Never see any in normal driving or wot driving. Link to comment Share on other sites More sharing options...
Spec B Posted July 15, 2009 Share Posted July 15, 2009 Ahh...good! Thanks. Link to comment Share on other sites More sharing options...
NSFW Posted July 15, 2009 Share Posted July 15, 2009 Is this normal behavior? For the most part, it only happens in nuetral. It would be great of someone could quickly log roughness and hold the RPM at 2500 while in nuetral and see if they get similar results. I have 25K miles, no oil consumption and no other symptoms. I'll check. I notice the same thing you described at idle, and I suspect my bigger injectors are at least part of the reason. So, if those of you logging roughness could do it at idle for 30 seconds or so, and let me know what you find, I'd appreciate it. I'll report back with my findings at 2500. I know the counts stay at zero in cruise but I've never looked at 2500 in neutral prior to this... Link to comment Share on other sites More sharing options...
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