sgt Posted November 14, 2006 Share Posted November 14, 2006 Yeah, I still have the stock header. I drove for about 20 mins sampling for about 5-8 mins at a time. I was able to recreate the stumble consistently but saw almost nothing in the logs. Kinda frustrating. Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 14, 2006 Author Share Posted November 14, 2006 have you tried interrupting the log right after the stumble? Link to comment Share on other sites More sharing options...
sgt Posted November 14, 2006 Share Posted November 14, 2006 Im pretty sure the stumble is caused by a temporary lean condition which I can see in the logs. I would think that this is caused by tip in, however the problem is that its not always accompanied by a corresponding TPS delta. Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 14, 2006 Author Share Posted November 14, 2006 do you have much more plumbing than stock? I suspect there are more tip-in tables which we don't have access to through ST. You might need to make adjustments to some of the other tables (assuming they exist) if you have a lot of plumbing. I had a look at a co-worker's AEM setup and he had three tip-in tables. One for dTPS, another for engine speed corrections, and a third for decay times. Link to comment Share on other sites More sharing options...
sgt Posted November 15, 2006 Share Posted November 15, 2006 Ive got the stock airbox but sti everything else. Engine Speed Correction!!!! That would be LOVELY!! Ive eliminated all of it above 2-2300rpm. Below I still have a few spots. Im sure that an engine speed map would help. Decay could also be useful. I dont mind throwing more fuel at it than I need to since I can build boost pretty much anytime from 1000-1500rpm and up. On a brighter note, gas mileage is still decent. Despite being off the board rich under boost(and this turbo is on boost a lot) Im still close to stock mpg. Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 19, 2006 Author Share Posted November 19, 2006 I was thinking about how one would tune AVCS for a different set of exhaust headers and it occured to me that the problem you are having might be due to your AVCS angles. At low RPMs, the intake valve closing event will have the dominant effect on cylinder filling. Unfortunately, we only have cam phasing control so the IV opening event has to move with the closing event. If we could control the IVC event separately, then that angle could be retarded to improve cylinder filling (only at low rpms when the mass of air in the runners really isn't moving fast). The problem we can run into is that retarding the IVC event also moves the IVO, increasing overlap. Now a compromise has to be made at low loads between charge dilution and not washing the fresh charge back by closing the IV ATDC. This could be the cause of your inconsistent results and lean running with no delta TPS. If the overlap is not right for the load/rpm you could have a case where a lot of exhaust gets back to the intake messing up the metering. It might also be possible that you are runnning at just the right angle to scavenge a bunch of fresh charge, during overlap, into the exhaust... messing up the O2 readings and causing Fuel Trim Immediate to go nuts (at higher loads/rpm this wouldn't be an issue as the ecm goes open loop). Have you tried setting the AVCS settings to 0? You would loose VE but it would be a good test to see if the angle is causing your trouble. Link to comment Share on other sites More sharing options...
sgt Posted November 19, 2006 Share Posted November 19, 2006 Actually, Ive made some great progress today. Tip in is near perfect and I was finally able to check the fueling up to 20psi so I can finally turn up the boost a bit. 14psi felt great but was getting a bit old =P Now I just need to put it on the dyno. Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 19, 2006 Author Share Posted November 19, 2006 good to hear I think I've finally gotten rid of the last bits of the wastegate flutter on my car. It took a bunch of logs to capture it but it turned out to be just 3 cells in the WGDC table which were off. Link to comment Share on other sites More sharing options...
sgt Posted November 19, 2006 Share Posted November 19, 2006 Help me out a bit, I still dont understand what flutter is. Flutter is when the wastegate flapper is inconsistently opening/closing right? Is it characterized by a sound? Fluctuating boost levels? Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 19, 2006 Author Share Posted November 19, 2006 WG flutter is an instability in the control loops which causes boost to oscillate around the target boost instead of settling at the desired steady state target. it sounds like heavy knock. I think most of the sound comes from the wg actuator opening and shutting the flap quickly. It is easiest to spot in the logs by looking at the turbo dynamics numbers. Whenever I get flutter, the turbo dynamics numbers flip between large negative and positive values a couple times per second. Link to comment Share on other sites More sharing options...
sgt Posted November 20, 2006 Share Posted November 20, 2006 I dont think I have a problem with that. I do however get a high pitched whine. I thought about an exhaust leak but I dont hear it any other time. I do smell it afterwards though so Im assuming its a leak of some sort. Link to comment Share on other sites More sharing options...
bugblatterbeast Posted November 27, 2006 Author Share Posted November 27, 2006 I slapped a set of headers on the car this weekend. I think I might have found a way to do some rough AVCS tuning before hitting the dyno. With the car in neutral, I rev up the engine to the rpm I want to adjust and trim the avcs advance while watching rpm and holding the throttle really still. As you trim the avcs setting the rpm will peak and fall off. Sometimes the increase is enough that you need to let off on the throttle a bit to stay in the same RPM cell. After the optimal values are found at low load, the trim is scaled and applied to the higher load regions. So far the WOT datalogs indicate that this method is working. Link to comment Share on other sites More sharing options...
Legacy_GT_Pilot Posted March 24, 2008 Share Posted March 24, 2008 I thought I'd re-open an old thread and attach my current Street Tuner map. This has been designed for my car which has a TD06-20G, meth, PE850's, AVO intake, Perrin TMIC and a few other goodies. Boost is targeted to 22 psi (it creeps a little above this) and tapers slightly and AFRs target 12.2 ish with meth. I've also modified the throttle settings to more closely mimic the STI. Rename the file to *.stb and it will be viewable via Street Tuner. So far my car has been running great, and I'm really happy with the current tune. I'll be going to the track soon, and will post up times when I do. Dave ________ Vaporizer Wholesaler22psi_DW_Mar2308.pdf Link to comment Share on other sites More sharing options...
qikslvr Posted April 24, 2009 Share Posted April 24, 2009 Just saw this. Cool and Thanks! I'd like to take a look at it and I'll post up my winter 20g non-meth map that seems like it runs pretty much like yours. It would hit 20psi by 3.5K and 22+psi by 4K and hold it as long as I want. Right now I'm re-tuning boost as I lost 4psi due the temps going from the 40's to the 90's overnight. I had to pump my WGDC's way up to hold boost and now I think I'm heating the charge up too much right around the 5K RPM area. I've got a Labonte W/I kit in the garage that will probably go on this weekend. Then I can start working on getting some power back and compare notes with your map. Let's kick this pig! Link to comment Share on other sites More sharing options...
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