Thank you for that. Do you know what the threshold is for this? 50% TPS, 35%...... And is that something that is also adjustable? I would assume so, but you know what assuming can do.
So russjnco sees knock counts, when he gets them, in the 2800-3800 rpm range. Hmmmm... Do you do your own tuning with anything?(Ecuflash etc..) If it's something that is effecting performance or for that matter just bothers you, maybe you could have a bit of timing pulled through that range and check some more logs.
I guess that's the million dollar question, is that problem or is something that's just a product of a different tune? To me it's a little bit of a concern because if the Ecu is pulling timing at that point then I'm assuming that's costing me a bit of power?
I am using Ecuflash software with a map that was provided by a vendor.
No, I don't know what the cutoff is, and I don't think there is a setting for it. With an SAFC, you can set it, but I haven't seen (or heard of) there being one in the ECU. You would think there is, but I just haven't encountered it.
We can both tune ourselves with EcuFlash, but it's not something most people play with, since it can be disastrous if done improperly. It's not as easy as picking an rpm and lowering the timing - it is based on RPM vs Load, and Load is not directly comparable to boost, although it is a function of boost. YOu have to know the proper load cell for changing timing and/or AFRs.
Cylinder pressures are greatest around 6k on the Evo, not around peak torque, although that can change with mods, turbos, etc. For Russ, he should be seeing peak cylinder pressure in the 6k area.
Actually, peak cylinder pressure is greatest at peak torque, not at peak HP.... that is why you ramp down the timming map as the car approaches peak torque and then ramp it back up beyond peak torque.
Peak torque = most powerful indevidual explosions in cylinder
Peak power = more explosions per second in the cylinder
Keith
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EVO 11.53 @ 123.37, Black WRX Wagon 13.62 @ 99.24
Actually, peak cylinder pressure is greatest at peak torque, not at peak HP.... that is why you ramp down the timming map as the car approaches peak torque and then ramp it back up beyond peak torque.
Peak torque = most powerful indevidual explosions in cylinder
Peak power = more explosions per second in the cylinder
Keith
Thank you for that. That was my original thought, but as I stated earlier I am still trying to soak up as much of this small displacement boosted stuff as possible. It also helps me in understanding why he gets the most knock in the very rpm range where peak torque(maximum cyl. press.) is occurring with the factory turbo.
Actually, peak cylinder pressure is greatest at peak torque, not at peak HP.... that is why you ramp down the timming map as the car approaches peak torque and then ramp it back up beyond peak torque.
Peak torque = most powerful indevidual explosions in cylinder
Peak power = more explosions per second in the cylinder
Keith
Hmm, that's contrary to what tuners say, but it's more likely that I misinterpreted the explanation or that I am just not remembering it properly. Whatever it is called, there is an event around 6k that causes us to need to fatten it up just a little. I've also witnessed how 10 straight Evos all spit out a puff of black smoke right at 6k, but it wasn't evident in the hp/tq curves, nor the AFR or boost curves. Whatever it is that causes that is what I'm referring. I had been told it was peak cylinder pressure, but maybe it's something else.
Hmm, that's contrary to what tuners say, but it's more likely that I misinterpreted the explanation or that I am just not remembering it properly. Whatever it is called, there is an event around 6k that causes us to need to fatten it up just a little. I've also witnessed how 10 straight Evos all spit out a puff of black smoke right at 6k, but it wasn't evident in the hp/tq curves, nor the AFR or boost curves. Whatever it is that causes that is what I'm referring. I had been told it was peak cylinder pressure, but maybe it's something else.
It probably is the RPM range where intake valve and exhaust valve overlap causes some kind of resonance in the intake manifold affecting the tune... I bet you it is the RPM with the highest exhaust manifold pressure, and the tuners add fuel for cooling purposes to compensate for reversion which may cause high temperatures in the cylinders.
This is just speculation, but does it sound like what you may have heard from the tunner?
Keith
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EVO 11.53 @ 123.37, Black WRX Wagon 13.62 @ 99.24
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