torqueaddict

I am back to the stock memcal, and I still get knock over 3000 RPM. Even with stock timing. I have 21 lb accel injectors, SD Vortec heads/intake, ZZ4 cam.

I am wondering could I be lean, or could I have a bad knock sensor. I am still new to interpreting data logs so any tips are greatly appreciated!
Here's what data log looks like:
RPM___Knocks_Retard___TPS____Load___O2__Temp__Fuel_Trim_LTerm-C__STerm-P
900___5______0________0.57___65____675__82.3__1_________160______-6.3
875___5______0________0.57___66___1026__82.3__1_________159______-7
900___5______0________0.57___61____857__82.3__1_________159______-8.6
900___5______0________0.57___61____857__82.3__1_________159______-10.2
850___5______0________0.57___62____955__82.3__1_________159______-10.2
825___5______0________2.06___173___826__82.3__8_________128______0
750___5______0________4.18___154___129__82.3__8_________128______0
1525__5______0________4.37___175___444__82.3__10________128______0
1775__5______0________4.37___183___444__82.3__14________128______0
1950__5______0________4.41___182___444__82.3__14________128______0
2125__5______0________4.43___186___444__82.3__14________128______0
2350__5______0________4.45___200___444__82.3__14________128______0
2725__5______0________4.45___205___444__82.3__15________128______0
3150__5______0________4.45___216___444__82.3__15________128______0
3650__6______4.2______4.45___221___444__82.3__15________128______0
4150__10_____16_______4.45___215___444__82.3__15________128______0
4550__14_____15.1_____3.9____207___444__82.3__15________128______0


also, if you want to, here's 2 runs I made.
http://members.bellatlantic.net/~dantill/arap_8_deg.csv
http://members.bellatlantic.net/~dan...ock_memcal.csv

randy4762

Before you get too into the problem being chip related, you should check something first. If your car has the heavy duty cooling fan setup, there is a second fan switch on the passenger side head. I believe it has a Black single wire connector. The car I just tuned for a friend was showing knock like yours, but the car still had audible knock while under full accelleration.
While looking at the knock sensor I noticed it had the black cooling fan connector hooked up to it instead of the proper knock sensor connector which was just hanging. (They both have the same style one pin connector) I switched them and now the knock retard worked great. Then tuning the car was a cinch. Previous to finding the problem I was working on the timing table for 2 days with no results. I always have to remind myself to go back to the basics when having weird problems.
Maybe this will help you.
I figured it is worth a try.
Randy

Fast355

iTrader: (2)

Engine looks to be running VERY LEAN.

JP86SS

iTrader: (1)

Do some part throttle tuning then go after the WOT stuff.
You'll just chase your tail otherwise.
Idle needs to have the o2 constants shifted to get rid of the 159 BLM.
Try reducing them by 40 and see what that gets you.

torqueaddict

Great! Thanks for all the advice.

I hate to ask such a newbie question but I searched and checked the constants in Tuner Pro- and I don't want to guess...

Which are the O2 Constants? Are the units mV? Is it really a table and not a constant??

thanks in advance!

JP86SS

iTrader: (1)

Idle has constants, off idle has tables. Its best to understand what your adjusting rather than having someone say "change this to this".
Look up in the tuning guide under 747 ecm "Fueling Logic (O2 swing points)"
That thread has RBob's writeup in it that explains how they work.
It will probably take several times before it all makes sense.
Check out the spreadsheet I've posted there for a graphical description and what changes will do to the windows" and crossing boundaries. Makes it a bit clearer to see the relationships.
If you do make changes to the off idle settings that I did (You'll see in the reading) check your temp table to be sure it doesn't already have values in it.
AUJP did not and at that time I assumed other $8D bins were the same. Never assume, its best to check

torqueaddict

I've reduced my knock quite a bit. My car is MAF, and stock is APYU3516.BIN
I can't find any constants to change the O2 at idle so I am assuming it's all in the table Rich/lean vs. airflow.

I reduced by 40, 80, 160, and 200 in that table. I still have L-Terms in the 130-160 range but my knock is much less.

I am thinking if I keep reducing the table, and maybe tailoring it to be less at certain gm/Sec I can fix things, but should I have to reduce this table so much?

Here's an example of my 200 mV reduced table:
RPM____Knock_Retard_TPS__Load__O2__Temp___Trim_LTerm-C_STerm-P_MPH
1150___17____0___1.29___157___169___78.5___13___148___7_____37
1150___17____0___1.29___153___142___78.5___13___148___7.8___37
1150___17____0___1.29___153___444___78.5___13___148___7.8___37
1150___17____0___1.29___158___697___78.5___13___148___7.8___37
1150___17____0___1.29___154___440___78.5___13___148___7.8___37
1175___17____0___1.29___155___453___78.5___13___148___7.8___37
1175___17____0___1.29___153___781___78.5___13___148___7.8___38
1175___17____0___1.29___151___471___79.3___13___148___7.8___38
1175___17____0___1.29___152___702___79.3___13___148___7.8___38
1200___17____0___1.29___152___302___79.3___13___148___7.8___38
1200___17____0___1.29___151___417___79.3___13___150___7.8___38
1200___17____0___1.29___150___440___79.3___13___150___7.8___38
1225___17____0___1.29___150___710___79.3___13___150___7.8___39
1200___17____0___1.29___151___817___79.3___13___150___7.8___39
1200___17____0___1.29___151___813___79.3___13___150___7.8___39
1225___17____0___1.29___148___209___79.3___13___150___7.8___39
1225___17____0___1.29___152___222___79.3___13___150___7.8___39
1225___17____0___1.29___150___364___79.3___13___150___7.8___39
1225___17____0___1.29___147___848___79.3___13___150___7.8___40
1225___17____0___1.29___146___608___79.3___13___150___7.8___40
1250___17____0___1.29___147___431___79.3___13___150___7.8___40
1250___17____0___1.29___149___715___79.3___13___152___7.8___40
1250___17____0___1.29___147___400___79.3___13___152___7.8___40
1250___17____0___1.29___149___604___79.3___13___152___7.8___40
1275___17____0___1.29___148___435___79.3___13___152___7.8___40
1275___17____0___1.29___150___440___79.3___13___152___7.8___41
1275___17____0___1.29___149___848___79.3___13___152___7.8___41
1300___17____0___1.29___146___515___80_____13___152___7.8___41
1300___17____0___1.29___150___324___80_____13___152___7.8___41
1300___17____0___1.27___146___426___80_____13___152___7.8___41
1275___17____0___0.57___75____417___80_____10___156___7.8___41
1275___17____0___0.57___49____364___80______6___146___0_____41
1300___17____0___0.57___48____502___80______6___146___0_____41
1275___17____0___0.57___48____839___80______6___146___0_____41
1300___17____0___0.57___50____573___80.8____6___146___0_____41
1300___17____0___0.57___49____768___80.8____6___146___0_____41
1275___17____0___0.57___48____231___80.8____6___146___0_____41
1275___17____0___0.57___49____231___80.8____6___146___0_____41
1275___17____0___0.57___49____124___80.8____6___146___0.8___41
1275___17____0___0.57___48____360___80.8____6___146___1.6___41
1275___17____0___0.57___48____115___80.8____6___146___3.1___41
1275___17____0___0.57___47____200___80.8____6___146___3.1___41
1250___17____0___0.57___46______9___80.8____6___146___3.9___41
1250___17____0___0.57___47_____13___80.8____6___146___4.7___41
1250___17____0___0.57___45_____89___81.5____2___146___5.5___41
1250___17____0___0.57___44____271___81.5____2___146___5.5___40
1275___17____0___0.57___43____258___81.5____2___146___5.5___40
1250___17____0___0.57___43_____13___81.5____2___146___5.5___40
1250___17____0___0.57___40_____67___82.3____2___146___7_____40
1250___17____0___0.57___41______9___82.3____2___146___0_____40
1250___17____0___0.57___41____107___82.3____2___146___0.8___40
1225___17____0___0.57___39_____80___82.3____2___146___0_____40
1225___17____0___0.57___39____155___82.3____2___146___0_____40
1225___17____0___0.57___38_____31___82.3____2___146___0_____39

torqueaddict

Still trying to reduce knock.

I swaped in LS1 injectors in place of the 21 lbs Accel ones. My BLMs are finally in line now, and I made some runs. Car does feel faster.

I still get knocks on WOT from about 2500 to 4800 RPM, somewhere in the order of 20, and timing is pulled. Don't know if I should have zero.

I tried increasing the base timing in the PROM 4 degrees (thus reducing it) and did some more testing. Same results. Finally I went into the spark table and reduced the whole thing by 15 degrees and saw a reduction in knock but I STILL got a few knock counts in the upper RPMS (3 or 4)! (and the car feels dead)

Should I be getting some timing pulled during WOT? Could the knocks be false? Could there be a failing part somewhere?

thanks in advance for any suggestions.

TUNGSTEN

It appears to me that your original long term fuel was right on. But your short term fuel is killing you. Fast 355 has a equation that you can use in conjunction with Tuner pro to fine tune your fuel. I'll try to find it. I used it and my fuel is dead on in long and short term fueling.

bigblock72

You probably should get yourself a wideband sensor, from the looks of the first table you're way lean and are going to hurt something. At the very least get your narrow band voltage over 800 mVolts at WOT. The safest thing is to have a wideband and tune it for 12.5:1 range, I'll bet when you get it richened up a little the knock counts will go way down. If you have to remove timing just remove it from the 100kpa (WOT) section of the spark map, NOT the entire map like you just did.