My log shows knock retard in the chart but zero in the channel table. It does show values in the channel Total Knock Retard. Do I have kr or not?
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My log shows knock retard in the chart but zero in the channel table. It does show values in the channel Total Knock Retard. Do I have kr or not?
Post a tune file for the more experienced guys to reference too.
I'm not familiar with LT4s, but is 24* of timing safe for 1.25g airmass and 170kpa? Seems high to me considering thats what my camaro runs at .8g airmass
Here's the tune file. This is a factory stock 2019 A8 Z06 tune.Quote:
Originally Posted by ShaneB
Yes, stock LT4's run up into 24 degrees near redline. You wont see this much timing unless conditions are optimal though. (PS I didn't look at OP's logs. Can't answer question without the tune.)Quote:
Originally Posted by ShaneB
1.25g is airmass for a sueprcharged LT4 at WOT. .80g airmass is an LT1 at WOT. Obviously the non supercharged motor has a lower airmass.
I didn't think the tune would be necessary for an answer to my original question. But the log and tune are both posted now.Quote:
Originally Posted by TriPinTaZ
I understand that, that's why I said it in my original post lol, didn't need explaining that a supercharger would cause higher airmass. But a quick google search finding that the LT4 has a cr of 10:1 vs LT1 11.5:1 explains same timing on boost.Quote:
Originally Posted by TriPinTaZ
OP, didn't know what someone with more experience would want to look at, figured it would be useful :shrug:
Your post didn't mention that you had a stock tune. But your Datalog title shows that you are not stock. Based on that I did not know if there were any alterations to your tune that would affect KR.Quote:
Originally Posted by 8850
The KR in your log looks like it could be from the Static Retard vs RPM vs Cyl table. So technically not KR but the stock tune in ECU pulls timing from a specific Cylinder(#1 in tune) regardless of real KR or not as there is a Cylinder that gets the least amount of fuel. It's not actually Cyl #1 when looking at the physical engine, its just labeled cyl #1 in the tune. You can see on that table that the KR value drops around 4800 as does your value (2.5 to 1.5) in your datalog.
Typically real KR shows up as a spike, then tapers down per the recovery rate as KR disappears. Yours never really falls off, it just seems to follow the Static Knock table. I wouldn't be worried about it. Your Datalog looks safe. A tune would get you more power though.
Thanks for the explanation! Yes, I am still on the stock tune in an attempt to save my warranty for now. Car only has right at 800 miles on it. No doubt tuning would give more power. I do have the aFe intake, Katech ported throttle body and a Borla catless mid pipe for mods so far. This may be about all I can go without tuning.Quote:
Originally Posted by TriPinTaZ
With tuning maybe best to zero out the static retard table and run a little richer than my current data? I see where it drops from 5 to 3 at 4800.
Still not sure why the table and chart don't reflect the same numbers regardless. But I suppose it is what it is. Thanks again!
Quote:
Originally Posted by 8850
I suspect there is a multiplier table that hasn't been defined in HP tuners yet that would multiply against the static retard table. This would explain why the value pulled isn't necessarily the value in the table.