Chasing a part throttle knock before boost.
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I made all the values in the table the same. It seemed to help some. I get less knock retard now and can actually keep some spark advance in boost. and finally start getting above 4800-5k rpm. It's still going lean as it approaches PE though, moved the kpa to 80, showed up at 75, back to 90, showes up at 85. I cannot hear knock, I bought some tube and crap to make knock phones just to be sure. I'm rookie as hell with his hp tuners stuff and EFI but it seems like some kind of parameter is causing this It might be a single fast knock and over with the knock retard and im not hearing it. But the fact it moves around like this just feels like there is some setting im missing thats forcing it to do this, like if it drops lean to fast real quick is there something that catches that and retards the timing before it knocks? Like something predictive?
Last tune and scan included
Last tune and scan included
Last edited by LetsTurboSomething; Jun 30, 2019 at 01:37 AM.
If transient adjustments don't help any, make the VE table rich at the kPa just prior to PE activation and see how that helps, also richen the VE table at that exact Kpa you enter PE. Worth trying as it just may work. Multiply the VE cells in the kPa prior to your PE engagement by 1.10 and see if that helps your lean PE transition point. At first I thought maybe it was your exhaust pipe hitting but if it consistently goes lean, that's most likely the culprit for the KR.
Last edited by foxsl; Jun 30, 2019 at 02:29 AM.
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Well, i got into the torque management stuff. Took away all its ability to retard timing form too much torque, turned the max knock retard inside of PE or BE to 0.
Holy smokes. So much power and its capped at about 6psi because the snow performance controller is a giant POS and only works intermittently about half the time. But 6psi seems safe, it has high octane in it but I about went through the whole tank today sorting this mess out. So this seems like a ugly band-aid of a fix. I basically copied what Denmah was doing in a bunch of 5.3 turbo junk yard builds. All his tunes looked to have knock retard inside of PE turned off.
log and tune included
Holy smokes. So much power and its capped at about 6psi because the snow performance controller is a giant POS and only works intermittently about half the time. But 6psi seems safe, it has high octane in it but I about went through the whole tank today sorting this mess out. So this seems like a ugly band-aid of a fix. I basically copied what Denmah was doing in a bunch of 5.3 turbo junk yard builds. All his tunes looked to have knock retard inside of PE turned off.
log and tune included
Last edited by LetsTurboSomething; Jun 30, 2019 at 04:35 AM.
Well, i got into the torque management stuff. Took away all its ability to retard timing form too much torque, turned the max knock retard inside of PE or BE to 0.
Holy smokes. So much power and its capped at about 6psi because the snow performance controller is a giant POS and only works intermittently about half the time. But 6psi seems safe, it has high octane in it but I about went through the whole tank today sorting this mess out. So this seems like a ugly band-aid of a fix. I basically copied what Denmah was doing in a bunch of 5.3 turbo junk yard builds. All his tunes looked to have knock retard inside of PE turned off.
log and tune included
Holy smokes. So much power and its capped at about 6psi because the snow performance controller is a giant POS and only works intermittently about half the time. But 6psi seems safe, it has high octane in it but I about went through the whole tank today sorting this mess out. So this seems like a ugly band-aid of a fix. I basically copied what Denmah was doing in a bunch of 5.3 turbo junk yard builds. All his tunes looked to have knock retard inside of PE turned off.
log and tune included
Last edited by foxsl; Jun 30, 2019 at 09:51 AM.
hey matt have you considered maybe your tuner is a kook? 
so the transient fueling can be really hard to tune on decaps, especially since the mechanical changes to the injector creates a way different voltage offset curve and deadtime values. I really only help people with decaps like matt here who actually groks how a motor works.
as for the data I used in the tune for those injectors....its what I and a couple friends have developed for use with those decaps to medium success. we have gone to 600 wheel on pump 93 no meth....but they always leave something to be desired in driveability....and they seem to let afr wander as they heat soak.
anyways sorry for the ramble. great ideas FoxSL
I hate the parts-cannon approach but I think switching those knock sensors & harness out would be my next move.
Keep on it Matt, you're way ahead of the curve as far as most folks I help. You'll be teaching me stuff in a couple week without a doubt
so the transient fueling can be really hard to tune on decaps, especially since the mechanical changes to the injector creates a way different voltage offset curve and deadtime values. I really only help people with decaps like matt here who actually groks how a motor works.
as for the data I used in the tune for those injectors....its what I and a couple friends have developed for use with those decaps to medium success. we have gone to 600 wheel on pump 93 no meth....but they always leave something to be desired in driveability....and they seem to let afr wander as they heat soak.
anyways sorry for the ramble. great ideas FoxSL
I hate the parts-cannon approach but I think switching those knock sensors & harness out would be my next move.
Keep on it Matt, you're way ahead of the curve as far as most folks I help. You'll be teaching me stuff in a couple week without a doubt
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I really dont want to keep it this way lol. Like i said, big ol’ band aid i got to last night but it did give me a bit of info. The knock retard didn’t show up so it was only happening in PE. But before i tried that it kept looking like it happened 5 kpa before PE. Would it be safe to assume since i changed that knock retard inside PE that its really strong evidence its a PE transition issue?...or bad sensors.
not that my ears are better than the vcm but i can hear knock. I had 90 in it, i had 100 octane in it. I never heard a single knock since I started tuning it.
but I’ll probably be buying some new ones today anyway.
You Got me close enough the local dyno tuner turned me away. If you’re a kook it must be the good kind lol.
not that my ears are better than the vcm but i can hear knock. I had 90 in it, i had 100 octane in it. I never heard a single knock since I started tuning it.
but I’ll probably be buying some new ones today anyway.
You Got me close enough the local dyno tuner turned me away. If you’re a kook it must be the good kind lol.
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hey matt have you considered maybe your tuner is a kook?
so the transient fueling can be really hard to tune on decaps, especially since the mechanical changes to the injector creates a way different voltage offset curve and deadtime values. I really only help people with decaps like matt here who actually groks how a motor works.
as for the data I used in the tune for those injectors....its what I and a couple friends have developed for use with those decaps to medium success. we have gone to 600 wheel on pump 93 no meth....but they always leave something to be desired in driveability....and they seem to let afr wander as they heat soak.
anyways sorry for the ramble. great ideas FoxSL
I hate the parts-cannon approach but I think switching those knock sensors & harness out would be my next move.
Keep on it Matt, you're way ahead of the curve as far as most folks I help. You'll be teaching me stuff in a couple week without a doubt
so the transient fueling can be really hard to tune on decaps, especially since the mechanical changes to the injector creates a way different voltage offset curve and deadtime values. I really only help people with decaps like matt here who actually groks how a motor works.
as for the data I used in the tune for those injectors....its what I and a couple friends have developed for use with those decaps to medium success. we have gone to 600 wheel on pump 93 no meth....but they always leave something to be desired in driveability....and they seem to let afr wander as they heat soak.
anyways sorry for the ramble. great ideas FoxSL
I hate the parts-cannon approach but I think switching those knock sensors & harness out would be my next move.
Keep on it Matt, you're way ahead of the curve as far as most folks I help. You'll be teaching me stuff in a couple week without a doubt
All the other tables are fixed like that Foxsl, the only one i found not was the FPR and I'll chalk that up to probably not mentioning the FPR I had because i stuck and automotive high flow up to the stock non-return setup (way overkill) but i wanted to leave it easy to change fuel rails and injectors later when i get the stones for more HP.
Bought two new knock sensors and a harness today and im off to put that crap on. lol I hope they are bad now because these suckers are not cheap as far as sensors go.
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Now that I think about it after you mentioning the wandering AF with heat soak that might explain the wandering AF at cruise i get. I kept smoothing and smoothing but i could keep it in a single cell perfectly smoothed around it and the AF would go back and forth between 14.1 and 15.1. Which changes the pitch of the engine without the rpm changing and will drive you insane if you're used to tuning with your ears a lot like I am.
All the other tables are fixed like that Foxsl, the only one i found not was the FPR and I'll chalk that up to probably not mentioning the FPR I had because i stuck and automotive high flow up to the stock non-return setup (way overkill) but i wanted to leave it easy to change fuel rails and injectors later when i get the stones for more HP.
Bought two new knock sensors and a harness today and im off to put that crap on. lol I hope they are bad now because these suckers are not cheap as far as sensors go.
All the other tables are fixed like that Foxsl, the only one i found not was the FPR and I'll chalk that up to probably not mentioning the FPR I had because i stuck and automotive high flow up to the stock non-return setup (way overkill) but i wanted to leave it easy to change fuel rails and injectors later when i get the stones for more HP.
Bought two new knock sensors and a harness today and im off to put that crap on. lol I hope they are bad now because these suckers are not cheap as far as sensors go.
I am pretty sure they are, or something is up in that department at least in my opinion. You said you were on 100 octane and still had knock? Technically, by definition, that's simply not possible, barring any ridiculous other factors like insane boost or spark values, which simply isn't the case. Octane is defined as "resistance to knock" and with 100, then it is 100% resistant. That should point you to the sensors for sure, either mechanically or in the tune. It's good you kept stabbing at it with tuning changes, as I think there is a ton of great info in here, and many can learn from this. It just sounded and looked to me like sensors were the issue from the start here. Hopefully new ones do the trick. Make sure you torque em right though... I've made that mistake before.
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I am pretty sure they are, or something is up in that department at least in my opinion. You said you were on 100 octane and still had knock? Technically, by definition, that's simply not possible, barring any ridiculous other factors like insane boost or spark values, which simply isn't the case. Octane is defined as "resistance to knock" and with 100, then it is 100% resistant. That should point you to the sensors for sure, either mechanically or in the tune. It's good you kept stabbing at it with tuning changes, as I think there is a ton of great info in here, and many can learn from this. It just sounded and looked to me like sensors were the issue from the start here. Hopefully new ones do the trick. Make sure you torque em right though... I've made that mistake before.
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Soooo.. the knock sensors. I don’t think they were plugged in. 🙁
took the manifold off enough to get at them, unplugged the sensor from the harness then pulled on the harness to unplug it and it came right to me attached to nothing. Which would maybe explain why this **** felt like some predictive thing the computer was doing. Because ya for a stock engine to knock on 100 would have to have a few millimeters of carbon on the pistons.
got it fixed. Got the sensors all set back to normal sensitivity. So far only one ping at 105kpa. Knocked 2 degrees off the high octane table in the spot and it hasn’t come back.
90 octane back in it, 7psi. No pings anywhere.
took the manifold off enough to get at them, unplugged the sensor from the harness then pulled on the harness to unplug it and it came right to me attached to nothing. Which would maybe explain why this **** felt like some predictive thing the computer was doing. Because ya for a stock engine to knock on 100 would have to have a few millimeters of carbon on the pistons.
got it fixed. Got the sensors all set back to normal sensitivity. So far only one ping at 105kpa. Knocked 2 degrees off the high octane table in the spot and it hasn’t come back.
90 octane back in it, 7psi. No pings anywhere.
Last edited by LetsTurboSomething; Jun 30, 2019 at 09:25 PM.
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I got this sucker up to about 9-10 psi tonight and it was just singing like an angel.And that is on 90ish. I had 4 gallons of that last fuel left and it was 98-100. With 15 gallons of 90 that leave it with maybe 91 in the tank right now so im being conservative with timing and watching like a hawk. In the 105kpa range i had theknock retard ping once and all it took was 1 degree, I took 2 degrees out from that spot and it never came back.
Scan here from 10psi if anyone wants to glance at it and see if im missing anything glaringly obvious.
I'll creep up a lil bit more but i need to wait on snow perf to get back to me about the controller unit. I don't trust it enough to rely on it at this point. Dang thing keeps locking up randomly.