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iNVAR

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About iNVAR

  • Birthday 04/21/1980

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  • Location
    Brooklyn, NY
  • Car
    05 LGT 5MT Stg2 custom

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    Nerd^2

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  1. Are you shifting very quickly? Also, a good custom tune will get you improved performance too, so that's in addition to the safety factor with the knock. You can do the tune in whatever weather you want, and the are compensation tables built in, but may require a little tweak when the weather changes. I did my own car in the spring, so when summer came I had to tweak the hot side of my compensation table to hit the targets. Then when winter came, I tweaked the cold side to stop over post. Some tuners don't even tweak the hot side though, so you end up not hitting your boost target in much hotter weather. It's safe that way though and you really don't eek out that much added performance from our tiny turbo and an extra pound of boost in the higher RPM range in 120 degree weather.
  2. There's nothing concerning to me as far as knock goes in the cruising log. You only have 1 feedback knock event, and it's not even when you're on the throttle, so don't worry about that one. I get those from time to time. The other event in fine learning is also very low load, nothing I'd be concerned about. Your WOT log, on the other hand, is concerning as you are in heavy boost, and actually overboost. To answer your question about what causes it, it happens because: 1) It's an OTS map, so it's one size fits all. Every car is different and as such will respond to a map differently. 2) It's also very cold. In cold weather (your intake temp only reads 34 here) boost come up very quickly. As such, your car is overshooting the 16.5 target and there is too much timing advance for the higher boost you are seeing. Solution? Get a custom tune. That's really the only way to fix it because I don't see a LWG (Low Wastegate) map available on COBB's site anymore. A custom tune can fix your knock in a few different or combined ways depending on the tuner: 1) Adjust the compensation table for WGDC to be lower overall. 2) Pull timing where you are seeing knock. 3) Adjust Turbo Dynamics to prevent overshoot. 4) Add fuel where you are seeing knock. 5) Make the boost target curve smoother to prevent overshoot. 6) Adjust WGDC tables.
  3. -12 and -4 are pretty significant knock events. You need logs.
  4. *bump* My steering had the exact symptoms everyone described here. I noticed the pump was wet where the hose was and when I popped open the reservoir I could see bubbles/foam inside. I ordered two (1 extra) of 34439FG000 as the OP suggested and today, I tackled the job. It is a VERY straightforward procedure. Remove engine cover. Remove engine cover mounting bracket from front (10mm and 12mm bolt). Remove inlet bolt (10mm) and immediately lift hose up to stop fluid from gushing out. Remove washer. Replace washer. Put inlet back in and torque down. Some of you guys mentioned putting the washer inside of the pump and then shoving the inlet in afterwards. I gave that a go but decided to just put the washer on the inlet directly and reinstall. I was afraid at first that this wasn't the problem with mine because when I removed the washer, it didn't seem shriveled up or dry or cracked or anything, but everything buttoned back up just fine and voila! No more leaking. Steering isn't squealing anymore and the reservoir isn't bubbling/foaming. Topped it back off a bit and all is well! Thanks OP and everyone else.
  5. Hey, so with all the flashing you've been doing, have you given your ECU a chance to settle in on fuel trims? I mean REEEEEEEEEEALLY settle into them. When I was tuning for boost a while ago, I would make adjustments on nearly a daily basis. Sometimes I would do it over the course of a few days. I had what I thought was a knock free map. Even after leaving a map on for a week, fuel trims seemed pretty stable and were knock free. Timing curved was good, boost hit quick and fast with the right amount of TD intervention. I left the map on and considered my work complete (with something like 150-200 revisions under my belt). Over the course of a few months, I noticed that my LTFT D was going negative. Not a huge amount, but still, going negative. After leaving the map on for half a year, I noticed that D had definitely gone negative (about -7 %) and knock had started showing up in my higher load columns, probably as a result of going lean in OL. You're making some huge changes to your fueling map, and I see that your map is significantly leaner than mine. I only caution you that what you see now (knock free) may not stay that way over the course of months down the line. Because it takes so many months for my LTFT to trend negative too, chasing down a potential "leak" (if that's what's causing it) is really, really, really hard too because I can't very well go fixing something and then waiting 6 months to see if my LTFT goes negative again. Just saying...be careful with leaning out things.
  6. Warming up in your driveway isn't the same as warming up while driving. Don't forget about things like your transmission, wheel bearings, etc.. Thicker fluid = higher resistance.
  7. Sorry, too much reading, didn't go back, but have you considered generally that: 1) Colder weather means your car takes longer to warm up even while driving and therefore while the engine is colder it's much less efficient 2) Idle speed is higher and for a longer period of time so those stop signs and lights and the seconds before you pull out of your driveway add up to a lot of gas
  8. Oops, sorry, I didn't read his earlier posts about having reduced fuel economy. I was only addressing the part where he asked why the car produces more power in the cold, which is explained by air density.
  9. If you look at your MAF (g/s) reading in a datalog for a given pressure at a given RPM (say 18 PSI @ 4000), you are ingesting more air during colder temperatures. Cold air is denser.
  10. Ah, well, there you have it. So 7-8PSI doesn't open the WG door 100%... it just opens it enough to keep boost in check at that amount. So in theory, you could get a weaker actuator and reduce WG boost down even more, lol.
  11. Hmm, I did some more research and neither of us is 100% right about this.... The strength of a spring is measured using a spring constant K = F/L (or D) which is Force divided by Length/Distance stretched. Not PSI. The problem is that there is no way to directly convert the amount of boost seen (PSI) to the amount of force the spring sees without knowing the amount of surface area the inside of the actuator exposes to the boost pressure. We need that number to figure out how many actual pounds of force is actually applied to the spring by a certain amount of PSI boost. But you're absolutely right, if it's operates linearly, it'll actually start opening as soon as ANY pressure (even a small amount) is applied to it so it seems I was mistaken about this. As far as the wastegate being open 100% at 7PSI or 8PSI, I'm actually not sure if this is the case. This would imply that the turbo's WG boost number is being determined by the size of the WG exhaust opening. MY feeling on the matter is that the WG opens up more and more as the turbo attempts to generate more boost, and so it keeps it in check at around the 7-8PSI range. A way to test this would be to completely disconnect the WG actuator and leave the WG door free swinging therefore allowing as much exhaust to bypass the turbine as possible. I wonder how it would produce.
  12. You have the concept correct but it’s important for you and others to understand this: Your boost control system has absolutely NO ability to open your wastegate until you are actually generating boost equal to or greater than the spring pressure. What this means is that below about 7 or 8 PSI, you really can’t prevent your turbo from spooling. What is also means is that your targets below 7 or 8 PSI don’t really mean anything. You will get to 7 PSI at 0WGDC just as fast as you would get there at 100 WGDC or 1000 WGDC because at below 7 PSI the pressure is not high enough to affect the actuator. If you properly adjust the boost control activation thresholds, then you won’t get annoying issues with Turbo Dynamics Integral and Proportional trying to compensate by needlessly adding or pulling WGDC. This will especially correct issues with TD Integral 'Windup'. My activation threshold is currently at Disable Below 6.95 and Enable Above 7.50. When I am cruising, I have a huge boost error, but that doesn’t matter because boost control isn’t enabled. And there’s nothing it could do even if it were enabled anyway. Putting -10 in there likely won’t make a difference though anyway because stock threshold is still around target 2 PSI. 2 port (bleed type) boost controllers bleed. 3 ports (interrupt) type don’t bleed: they completely divert, hence the name ‘interrupt’. When a 2 port bleeds pressure away from the WGDC, it’s just opening a value and allowing boost to ‘bleed’ back to the intake tract. This means that no matter what, the WG actuator will still see a small amount of pressure coming. “Bleeding” is basically creating a leak for the pressure to escape back to the intake. A 3 port, on the other hand, actually redirects pressure away from the WG completely. This gives you more fine and immediate control over the actuator. In theory, it’ll feel exactly the same while spooling, IF you have an interrupt boost controller (3 port) and the WGDC values and targets are properly set up.
  13. What's the log interval like on that? Interval on my vagcom is about 95ms with about 15 parameters
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