So yeah reading about knock for a noob seems to breaking down as such.

1) Real knock - pre-ignition and detonation

2) False knock - something hitting the block setting off the sensor.

Not sure what I am dealing with here.

So a couple questions.

1) Evoscan knock sum - each count is equal to one knock event?

2) When the car pulls 1 degree of timing isn't that equal to 3 counts?

3) Spark plugs gapped at the factory. Should I pull them and ensure proper gap. (Probably good to pull them just to see what the condition is in there (lean, rich, etc on all cylinders)

4) When you do a pull. If I am at a low rpm at say 2000 exactly do I just pound it or roll the throttle on. (The reason I ask this one is it really affects my logs)

5) So I go and do 3 runs my plain 3rd gear pulls have a couple 2's and 3's. But then I do a log from 1-2-3 redlining each gear and I have a couple random 1's and nothing more. Same with a 4 gear pull. Why the difference?

6) When chasing down knock, If my AFR's are right then I am just backing off timing at this point, right?

Thanks for the info. Still learning.

 

Lots of things could cause knock, aggressive mivec settings, too much boost for the octane level, bad gas, etc, etc. I was getting alot of inconsistent knock during WOT, so i switched gas stations and it seems to knock alot less now.

 

Yeah, the weird thing is that when I did the other pulls with no or little knock (1's) I had just filled the tank with a fresh batch of 93. Maybe thats part of the mystery right there.

 

1) no - think of it as a magnitude or loudness indicator...

2) 1 knocksum = 0.35 timing retard, therefore 3knocksum will pull out 1 and a tiny bit of timing.

3) if you want

4) I just go WOT with no rolling into it, sometimes a built motor will knock when you do that because of bad tolerances...

5) because your hitting different load cells

6) what do you consider a right AFR? whats your boost set at? what fuel are you using?

 

^^^^

5) because your hitting different load cells
Okay. So which is the better indicator of how the engine is running. i.e.. Wound out through multiple gears vs. 3rd gear. Why is 3rd gear the standard. Or is it just a controlled set of load cells for diagnostics.

6) what do you consider a right AFR? whats your boost set at? what fuel are you using?

I am thinking that 11-11.5 is right (but what do I know I'm a noob) My boost is 24 tapering to 21. I am using 93-94

 

4th gear pulls are the best, they load up the engine properly and run long enough for heat to develop..

trouble is 4th maxes out at 180km/h which is too fast/dangerous for road tuning...

that said I will also do some running through the gears and modify the tune if I see a problem

good stuff ...

 

Yeah 4 gear is pretty fast for sure!

Thanks Tephra

Here are two separate runs both 3rd gear

RPM	TimingAdv	KnockSum	KnockRetard
2062.5	39	0	255
1937.5	46	0	255
1843.75	38	0	255
1500	30	0	255
1562.5	28	0	255
1562.5	21	0	255
1593.75	20	0	255
1625	19	0	255
1687.5	20	0	255
1718.75	20	0	255
1750	22	0	255
1812.5	24	0	255
1843.75	24	0	255
1875	26	0	255
1937.5	25	0	255
1968.75	25	0	255
2000	25	0	255
2031.25	25	0	255
2062.5	25	0	255
2093.75	25	0	255
2125	26	0	255
2187.5	26	0	255
2218.75	25	0	255
2250	24	0	255
2281.25	24	0	255
2343.75	24	0	255
2375	24	0	255
2406.25	23	0	255
2468.75	24	0	255
2500	21	0	255
2593.75	16	0	255
2656.25	13	0	255
2750	10	1	255
2906.25	9	0	255
3093.75	7	0	255
3250	5	0	255
3468.75	7	0	255
3718.75	8	0	255
3968.75	9	0	255
4156.25	9	0	255
4343.75	10	0	255
4593.75	10	0	255
4781.25	11	0	255
5000	10	1	255
5187.5	10	1	255
5375	11	1	255
5562.5	11	1	255
5718.75	13	0	255
5906.25	13	0	255
6062.5	13	0	255
6250	14	0	255
6406.25	13	2	255
6593.75	13	2	255
6718.75	14	1	255
6875	15	1	255
7000	15	1	255
7093.75	15	1	255
7156.25	15	1	255
7250	17	0	255
7406.25	17	0	255
7500	17	0	255
7562.5	17	0	255
7562.5	5	0	255
7031.25	20	0	255
6656.25	33	0	255

RPM	TimingAdv	KnockSum	KnockRetard
1843.75	36	0	255
1843.75	36	0	255
1875	36	0	255
1875	36	0	255
1875	36	0	255
1875	36	0	255
1906.25	34	0	255
1937.5	28	0	255
1968.75	23	0	255
2000	21	0	255
2062.5	21	0	255
2093.75	21	0	255
2156.25	20	0	255
2218.75	20	0	255
2312.5	17	0	255
2375	15	0	255
2468.75	14	0	255
2562.5	12	1	255
2687.5	11	0	255
2875	8	0	255
3062.5	3	0	255
3250	4	0	255
3406.25	5	0	255
3687.5	7	0	255
3937.5	9	0	255
4156.25	8	2	255
4375	9	2	255
4593.75	9	3	255
4812.5	10	2	255
5031.25	10	2	255
5156.25	10	2	255
5312.5	11	1	255
5531.25	11	1	255
5687.5	11	1	255
5843.75	12	1	255
6031.25	13	0	255
6218.75	14	0	255
6375	14	0	255
6562.5	14	0	255
6687.5	14	0	255
6843.75	14	2	255
6906.25	7	0	255
6437.5	26	0	255

 

I had the same problem at WOT with my build block It will knock so we pull timing out and is no more knock but the question is that is this is like a false knock ?? cause my engine build is rated to 680 + and i am only at 521.

 

Doesn't a stock everything as purchased read levels of knock as well?

 

Your only real answer between real / false knock is det cans or actually listening to the motor yourself. If you have it strapped down and can stand next to the engine bay it sounds like a hammer hitting the block, however that is not always easy for an untrained ear to hear.

There are other methods, but once set up that is the fastest and most reliable way to tell.

 

You need a WB. Could be chocking on the fuel and giving you that slight knock (known to happen).
And FYI, if you can hear knock it's too much. I've only heard it a couple times, sounds like a fast pinging (kinda like when you get home on a cold night and your exhaust starts cooling off quickly; only at a much faster tempo). Logs showed ks of 30+ on a really steep grade at low revs (easiest way to get knock)

 

Can you force knock?

Like when you are driving at say 60-70 MPH and then floor it(WOT) still in 5th. Would the load on the engine in that gear and being under the power band cause a knock situation on an otherwise well tuned car.

 

yes.

too much timing, too much boost, ****ty fuel, improper air/fuel ratio all cause knock

 

What I am refering to is high load on low rpm. I think that has little to do with what you just mentioned but more the fact of the stock turbo size + mivec timing creates spool with slower moving pistons. There for creating a knock situation.
There fore when driving if you don't down shift and floor the car you will create a high load + low rpm = overpressure and knock.

Yes or no?

 

ive noticed some roms have better support then others when it comes to the knock filter tables.

for example: 53050109 has everything in its xml..

Knock Sensitivity Load Threshold and
Knock Background Noise Multiplier

those are the only 2 tables you should need when adjusting sensor sensitivity.

and i see on this rom: 52680122

it has nothing .. none of these tables.. except it has 3d tables that are titled

knock filter #1 through 5

=======

are the 3d tables named knock filter actually real or are they mistyped table names?

and do we know the load threshold address and multiplier for the rom i mentioned above? 52680122

--------

Reason I ask, is because i have a 2008 time attack evo X that has prototype BC cams in it and it knocks just driving around and everything is 100% conservative and everything's all good in the car.. these damn cams are just so aggressive..

we get a clean pull every now and then but once it start at spool area it just creates the knock train and sensor becomes overly alert and from there everything goes to crap.

we put in c16 race gas also.. it is 100% false and confirmed with det cans and race fuel.

i pm'ed tephra but im sure he gets a million pm's.