am i incorrectly seeing knock? 2015 SC f-150

[rushdylan]

over the past few months i've been learning to tune the gen2 coyote platform with my TVS2650 f-150. i've had much success until i've began to add timing. at this moment im unsure if im seeing it retard timing or not. im still learning to understand the system as a whole and what its telling me. just based on searching through the vault; my spark tables appear to be quite safe but any move i make seems to populate the KnockCorrection channel with a negative number and i can only assume it is seeing knock and pulling timing. any help is appreciated
dylan_tune_V1.hpt
WOT_shift.hpl

[rryanfla]

You are getting 4-5(+) degrees of knock. positive knock is knock, negative knock= timing is being added to borderline tables. Are you running 93 octane?

[rushdylan]

91 octane (California). Hard to believe im getting that much knock at only 14/15* advance. Perhaps I should have a look at the knock sensor tables

[rryanfla]

I looked at your cam(IVO/EVC)angles while your in OP. Take a look at some other 5.0 TVS OP cam angles. I tried to post pics of my OP angles but the pics wouldn't upload. Just a WAG.

[rryanfla]

17 TVS AUTO Baseline.hpt

Take a look at OP in this tune. its a TVS tune. Hope it helps.

[txcharlie]

It's noise from the blower. Not sure about the 15+ calibration, but my '14 file had the knock sensors turned off by Roush. I went round and round and could not get rid of the KR. I was running E85 that tested 89% with the stock Roush spark tables(extremely conservative) and still saw 3-4* of random knock. It would detect knock and immediately try to advance the timing a fraction of a second later. Real knock will look like steps. The best advice I can give is to pull plugs after you logged knock and check for detonation. I now have a Whipple and do not have that issue.

[rryanfla]

Damm, Never thought of that. Pretty sound advice there.

[rushdylan]

It's noise from the blower. Not sure about the 15+ calibration, but my '14 file had the knock sensors turned off by Roush. I went round and round and could not get rid of the KR. I was running E85 that tested 89% with the stock Roush spark tables(extremely conservative) and still saw 3-4* of random knock. It would detect knock and immediately try to advance the timing a fraction of a second later. Real knock will look like steps. The best advice I can give is to pull plugs after you logged knock and check for detonation. I now have a Whipple and do not have that issue.

i was very curious about this. having supercharged other cars; i always picked up knock from the rotors and zeroed the knock tables but i am not an expert with the new coyote platforms so im unaware of the knock strategy and effectiveness. given that i use 91 (my kit must remain pretty smog legal(ish) ) i still need to log knock somehow other than my ear so ill have a look at the plugs as you mentioned. i've had very bad experiences with little amounts of knock and OEM subaru pistons so i am very cautious.

[txcharlie]

i was very curious about this. having supercharged other cars; i always picked up knock from the rotors and zeroed the knock tables but i am not an expert with the new coyote platforms so im unaware of the knock strategy and effectiveness. given that i use 91 (my kit must remain pretty smog legal(ish) ) i still need to log knock somehow other than my ear so ill have a look at the plugs as you mentioned. i've had very bad experiences with little amounts of knock and OEM subaru pistons so i am very cautious.

It's a very fine line between making good power and being safe. When I sought advice from others, no one would come out and say that it was false knock, but in my case, knowing the spark was stupid safe and using tested fuel, it could only be false knock from the blower noise. It's the very reason the Roush tune has extremely soft spark tables and the knock sensors are disabled. The Tuning School sells a Plex knock system that is supposed to only detect the frequency of real knock, but it's $1k. I never really pushed my spark tables with the Roush because in the back of my mind, I feared I may have been wrong with my diagnosis. Old school with pulling plugs is the only way I know to be safe when dealing with blower noise. People way smarter than me say not to jack with the knock sensitivity tables, so I never did.

[rushdylan]

Very much agreed. I know theres no way I was knocking that bad at that amount of timing advance. I found a 15+ roush file here on the forums recently and had a look at the knock sensor gain and it appeared to be even more senative than my current setup. Weird?


Edit: pulling 20% sensatuvity out after after pulling the plugs. Will report back with results.

[rushdylan]

So 20% made a drastic difference. It was able to hit my target of 17.5* advance without issue. From this point I'd like to bring the sensativity up until I see the knock again so I have a better idea of what we want from these sensors.

[LastPlace]

I think your going to damage your motor.

[[email protected]]

The best way imho is to put the knock sensors at stock, put high octane fuel that definitely wont knock from spark and then see if you still have knock. If you do have knock its mechanical if you dont then it was spark related. be careful, the timing a mustang can run vs a truck is entirely different based on weight alone. Dont try and give it anymore spark than it need just because you think it needs it.

[rushdylan]

I think your going to damage your motor.

The best way imho is to put the knock sensors at stock, put high octane fuel that definitely wont knock from spark and then see if you still have knock. If you do have knock its mechanical if you dont then it was spark related. be careful, the timing a mustang can run vs a truck is entirely different based on weight alone. Dont try and give it anymore spark than it need just because you think it needs it.

i am fairly confident that i am not seeing mechanical knock at 17.5* however i will of course take your reply into consideration; (the blower is loud) and i am still within roush/whipple timing but will try some 100 octane and report back. i understand 20% was a large percentage to reduce but was only done to prove the concept. if i cannot correctly tune the knock sensitivity then it will forever be pulling timing from false knock off the blower; no?

[RSlo]

Very much agreed. I know theres no way I was knocking that bad at that amount of timing advance. I found a 15+ roush file here on the forums recently and had a look at the knock sensor gain and it appeared to be even more senative than my current setup. Weird?


Edit: pulling 20% sensatuvity out after after pulling the plugs. Will report back with results.

So pulling 20% sensitivity is 20% numerically lower?? I’ve seen some tunes add 20% so numerically higher. I guess question being is the HPTUNERS table description correct? Thanks!

[rushdylan]

it defines a larger value being more sensitive. so having an average value of 24 in most cells (that are actually moving some air) and using 24 as my whole number; i know after some math that 20% of 24=4.8 so the new value being 19.2. it clearly worked but proves that there is still more work to be done and many graphs to study to understand what the mechanical knock looks like vs the blower noise.

[LastPlace]

Without something like a plex knock monitor, Your best test is a high octane fuel.

Your guessing without real data.

[RSlo]

it defines a larger value being more sensitive. so having an average value of 24 in most cells (that are actually moving some air) and using 24 as my whole number; i know after some math that 20% of 24=4.8 so the new value being 19.2. it clearly worked but proves that there is still more work to be done and many graphs to study to understand what the mechanical knock looks like vs the blower noise.

Thanks. I’ll play around with it this season. Once and awhile I’ll get some in 3rd gear but then totally fine through 4th. Running E85 with a P1X

[Ranger Coyote]

I have a Roush 727 on a 2016 GT and I can't run 91 without using octane booster with the stock Roush tune. When I run E85 I never get even a blip of false knock so I would be real careful adjusting your sensitivity.

[LastPlace]

I have a Roush 727 on a 2016 GT and I can't run 91 without using octane booster with the stock Roush tune. When I run E85 I never get even a blip of false knock so I would be real careful adjusting your sensitivity.

^^^ funny how all the fails knock goes away with e85.