boostboy:
Mine only does that when I have the min duty cycle on the turbo set to high and/or Wastegate Canister Pressure to Duty Cycle too aggressive.
Your turbo settings have been tampered with so I'd put everything under Wastegate, Feedforward and Proportional back to oem. I can't say I know exactly how these work but I have played with them a lot in my car and the oem settings are actually pretty good. When I mess with what's under Wastegate, Feedforward I don't really see bennies, it just screws it up. Unless I do it to match a higher min duty cycle, which you're not doing. But you no doubt have different canisters so I guess maybe copy the data from a car that has those same ones? Like your Wastegate Desired Stroke Position is VERY aggressive compared to oem and even 10% as much as you changed yours would cause me to overboost at part throttle. Ask me how I know
I assume by overboost at part throttle you're experiencing the same as I do, which isn't actual overboost but simply too much boost when not needed. Eg the intake is still under vacuum but the the Tbos are making 5psi. Or too much "TIP" as they call it. Mine has a TIP setting in there somewhere, which I bumped to the max of 37psi, which did nothing to help my problem. Imo a lot of things in there do nothing at all. Maybe they work on some other car but they don't tell you what your car uses and what it does not, so I've wated countless hours on things only to discover they do nadda. Or they do something very different than claimed.
The Wastegate Canister Pressure to Duty Cycle is another one I have to be careful with, or again, overboost at part throttle. That's the one just under Spring Constant. It seems to me it's a guide to command duty cycle, so the ECU says I want -10kpa canister pressure, based on all it's calcs, then looks at this chart. So in your case it says I'll give it 27.2% duty cycle to get there. The ECU has no way to see that pressure so it's relying on that chart. Since you have different turbos I suppose it's logical to assume different diaphrams and maybe all those values are too much.
Then it overboosts at part throttle before it can correct for the mistake, which is exactly what mine does if I set the values too aggressive. So I'd cut all the values in half, excluding the -80 and see how it responds. It should lower said part throttle boost nicely, then you can adjust up/down as needed. Your Proportional Gain could be turned up because imo it doesn't hurt anything and if your new Tbo is making too much boost in an unexpected zone then this will allow the ecu to respond quicker. You could also zero out your Derivative which will speed things up. I don't have an Intergal Time Constant but I'd just put it back to oem for now.
Then Min Duty Cycle, at the bottom left there named "Min Sol Protect". That one helps me greatly reduce turbo lag but it also cause part throttle overboost, and over boost period if set to high. If I set mine at 50% I'm right on the edge of both scenarios. And when it overboosts on either, the boost logic turns off and duty cycle goes to the minimum. If I have it set to 50% then I don't actually lose all my boost, compared to the oem setting which kills all boost. So if you want, you can bump that min # up like I did to minimize lag. It also keeps the wategates close most of the time so less wastegate hinge wear, which is an issue, at least on my car.
Then looking at your Torque to Load I think that's making it worse? I easily hit 50% load at part throttle under normal driving, and yours is set to suddenly go full throttle at that point. If putting at say 2-2500rpm that means a lotta boost asap, and if any of the settings above are wrong it'll overboost in a heatbeat. Well, it will on mine.
So to make Torque to Load work well in my car, the largest increase in Tq to Load is at max % row. In your case 100%. Then the row above, 90%, is blended between the the 80 and 100 so it isn't a sharp transition. Optionally you could blend, or interpolate, the 80 & 90% if you wanted. Imo no need to go below that because all the oem values at 70% and below are fine. Also, your Tq to Load values seem really high. Not sure what power/boost you're trying to hit but I suppose for now I'd limit 100% to 250? Just a straight 250 across the board at 100% and blend? Mine for example only goes to 80%, and I bump that to the max I want, then the 70% row just above it is a blend of 80 & 60. Done. Works perfectly.
Your Max Desired Load under Airflow claims to be based on Intake Air Temp? Mine is water temp. Weird, but point being that on mine it does have a big influence on torque and I actually use this to control wheel spin. But my numbers are much higher than oem, so the low #s I use to control spin are higher than the oem #'s. Then the rest of the #'s at 2500+rpm are more than double oem. Point being that on my car this chart is one that actually does something and at least for me it needs to be bumped up a lot, but can also limit where needed. So maybe your 2250 rpm #'s are too much, or too sudden a jump. I think your turbo settings are the cause but maybe this and the Tq to Load are too abrubt for part throttle to deal with when your Tbo settings are too agressive. I'd make this much more gentle, or oem, until you figure out your issue.
The stuff under Torque Management/Driver Demand is different than mine, so all I can really say is I'd put back to oem for now, unless you have that page figured out and know it's good. My throttle settings are basically oem except I lowered throttle response down low. For example oem was a 5% throttle position gave a 5% command, 20% = 20 etc. Since the other tune settings upset that and increased output, the car would jump at the slightest touch of the throttle. To tame that my 5% throttle position = 2% command, 10% = 5 etc, but 100% equals 100% which is all that really matters.
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Originally Posted by Schnell
My acceleration above 60 is better than stock, and 0-60 would be better if the throttle let it. It usually pauses mid way 0-60 so bad that when you play it back and watch the speedo it looks like I floored it to ~30-35, let off the gas completely for a second, then continued. Sometimes the speedo stops moving altogether during that time. If it did not do that I suspect 4sec or less?? 0-100 is ~9sec, and 120 ~12. That might just = 12.0 in the 1/4?