KR explained

[Vansquish]

I've been hoping to avoid this section, but unfortunately, here I am! I was checking that my MAF calibration was on-point given that we're starting to have some warmer weather and I just cleaned the filter on my SRI (less detritus = better flow), and decided to do a few little WOT runs to see how things were holding up on that end too.

The result...well...mixed at best.

I'm seeing KR up to 5.5 in the 1.6-1.8 load range, and between 4700 and 5700rpm. On my latest map I forgot to enable the knock sensor above 5700, so I'm assuming/extrapolating that it continued to knock up near the redline as well.

My map is based on a 91 Octane Stage 1, CpN OTS map from Cobb, but I've tweaked Boost, AFR, and timing per Abilor's/Bucker's guides. This is the first time I've seen this much knock at WOT, so I'm wondering if you guys think it might be transitory (spark plugs, bad gas, etc...), or something a little more serious.

Apologies in advance for the log. I took the knocking portions of my long-ass log and dumped them into a single CSV file with each separate occurrence separated by a single line gap.

Thanks in advance for any insights you might have!

EDIT:
For anyone looking for an example of what not to do, check my log.

I believe that my knock was real, but related to a few pretty easy-to-fix things (please let me know if I'm wrong).

1) I was running significantly too much timing in the mid-upper rev range given my modest mods.

2) BATs were reasonably high (100*-120*)

3) IAT was reasonably high as well (that's what I get for having an SRI).

At any rate, I flashed to a map with significantly less aggressive timing and now things are running more or less perfectly again (0-.35* knock), and on my last log, I made about 25lb-ft more (though 10whp less) than the more aggressive map.

[Mortose]

Originally Posted by bertrand_CX_7 hey guys sorry for the nob question, but I'm seeing late on my AP the KR reading 8.0 So I'm really not sure if this really means 8.0 of KR, that's why I'm asking just to make sure. The weird thing is that it's happening when cruising at the time I wasn't punching the car when I'm suddenly reading this on the AP. So no load on the engine when this is happening. My tuning is not completed yet. There is still the regular gas pump to be tune out. Anyone else seeing this?

I'm starting to see the same thing. Not NEARLY that high, but like 5.5* or lower. But mine only does it when the motor is "cold". once i've driven around a bit, it has a quick fit of KR, then i'm good for the rest of the day (unless i park for 8-10 hours). I've ran WOT, and seen a blink of .3 every once and a while, but never anything more.

I NEED ANSWERS. I'm running a Stage 2 91 SF+TIH+IC.

Side note: i did add some octane booster to this tank, so we will see.

[bertrand_CX_7]

Yeah, i got DJ Look into that. then got a reevised map that looks much better now.

I bearely See KRs now. I'll check what changed on that map and Update you.

[Mortose]

Thanks man.

[DickFitzwell]

good thread @Lex. starting my tune from @atvfreek tomorrow for 50/50 (assuming he thought my logs looked good enough to warrant this). looking forward to meeting you finally in a few weeks for the SOCAL NATOR dyno day; ill keep ya posted on what i find in my new tune

[Mortose]

Originally Posted by Mortose I'm starting to see the same thing. Not NEARLY that high, but like 5.5* or lower. But mine only does it when the motor is "cold". once i've driven around a bit, it has a quick fit of KR, then i'm good for the rest of the day (unless i park for 8-10 hours). I've ran WOT, and seen a blink of .3 every once and a while, but never anything more. I NEED ANSWERS. I'm running a Stage 2 91 SF+TIH+IC. Side note: i did add some octane booster to this tank, so we will see.

Update: Seems i MAY be getting hot spots. I found that if i drive out of boost for about 10 min, i can drive like normal and not get a single hint of KR.

Any in-site on this from the guru's?

[Lex]

Originally Posted by DickFitzwell good thread @Lex. starting my tune from @atvfreek tomorrow for 50/50 (assuming he thought my logs looked good enough to warrant this). looking forward to meeting you finally in a few weeks for the SOCAL NATOR dyno day; ill keep ya posted on what i find in my new tune

You're in good hands - you should make some solid power on the dyno!

[rfinkle2]

If injector seals are a suspect of false KR, is there a specific portion of the rev band in which KR would be reported or is it random?

[KevMS6]

How much knock can these cars handle before causing damage?

If timing is out causing knock of around 5* throughout WOT runs, can there be immediate engine damage?

[Lex]

Originally Posted by kevstewart• How much knock can these cars handle before causing damage? If timing is out causing knock of around 5* throughout WOT runs, can there be immediate engine damage?

Yes there can be damage. The longer you are in those conditions the more likelihood for damage.

[x09MS3GT]

Originally Posted by Lex Yes there can be damage. The longer you are in those conditions the more likelihood for damage.

If i ever once logged KR over 2 in my car at any time during WOT, i would pull over, turn the car off, kneel down by the front driver side quarter panel, and quietly apologize to my 2.3 DISI until I was deemed forgiven by the car Gods.

[KevMS6]

I wasn't out long, about 5 miles, consisting of a 3/4/5/6 4/5/6 and then slowly back home... Consistent knock in every run, every gear seeing around about 5

My normal timing is around 7, it was up around 20 this time however

Hopefully no damage done

[maddocx240]

hey im looking for a little help with my logs im seeing the last couple of days.. im on a stage 1 ots stock tune, only upgrade i have is kmd internals. my kr is all over the place. fuel pressure is good, my a/f ratios are a bit iffy as well.. it fluctuates from 11's to 12's.. im not sure whats going on, maybe one the tuning gurus on here can help me out..

[atvfreek]

Originally Posted by maddocx240 hey im looking for a little help with my logs im seeing the last couple of days.. im on a stage 1 ots stock tune, only upgrade i have is kmd internals. my kr is all over the place. fuel pressure is good, my a/f ratios are a bit iffy as well.. it fluctuates from 11's to 12's.. im not sure whats going on, maybe one the tuning gurus on here can help me out..

Your car is running a bit lean. Some OTS maps need a bit more work than others. Need to start with a good maf cal for both PT and WOT. Then adjust all your fuel tables to a conservative afr to start. Looks like you are running a good amount of timing, so that mixed with the lean/erratic afr's is causing the kr.

[Lex]

Originally Posted by kevstewart• I wasn't out long, about 5 miles, consisting of a 3/4/5/6 4/5/6 and then slowly back home... Consistent knock in every run, every gear seeing around about 5 My normal timing is around 7, it was up around 20 this time however Hopefully no damage done

This was a bug with VT. Make sure you upgrade to 1.7.2

[CWP_MS3]

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