So I have street tuning my Evo IX MR for the past week or so and have dialed in the AFR and boost curve to where I want it but I can't seem to tune out the knocking that occurs right before during and right after peak torque.

This is the scenario, I always do 4 pulls at the same location from 2300-2500 RPMs all the way to redline. 2 out of 4 the pulls will have the knock as pictured in my log below and the other two will be completely knock free. Its usually the first pull and the third pull where I see this knock. I honestly don't see how to tune this knock out or if I even should since there are never more than 2 counts. I am just wondering if anyone out there has experience with knock like this and what they did to alleviate it.

My mods are

-AMS TBE - testpipe
-LC-1 wideband
-Evoscan GPS
-Grimmspeed 3 port @ 22psi
-JDM MAP
-Tephramod V7
-ETS intake
-Walbro 255

-everything else stock

Note: Lean Spool is enabled

Below is my timing, fuel, desired boost (psi) and a recent datalog.









Thanks

Justin

 

1-2 counts of knock is fine... its not like its knocking 3-4counts and so on...

but from the look at things... its reading 5* then jumps 3* to 2* of timing... thats whats causing your knock...

 

What sux is if you look at my timing maps and the loadcalc, where would I reduce the 5 degrees at? Maybe at 2750 RPM and 180 kPA? I'm thinking the ECU interpolatez between loads during spool up? I think the 5 is coming from interpolation between the loadcalc between 147 and 215 @ 2750RPM on my datalog.

Looking at my map at 2750 RPMS, 5 degrees is located in the middle of 140 and 210 kPA. Would this mean that I would have to decrease timing in the 160-200 columns in order to induce a smooth timing transition?

 

you should rescale your maps... 100 through 180 by 10s... that way it will be smoother... PM ME

 

Did you set all three ignition maps the same? Also you need to upgrade your injectors imo, below 80% is ideal and your hitting 109% making them static and impacting the flow pattern. I honestly would turn down the boost until then, just my .02

 

I have the v7 tephramod, only 1 map for ignition. I hear ya on the IDC, I just got my PTE 680cc in the mail. I am installing an Aquamist kit here within the next week so the 680cc should be good.

 

I am going to try this ignition map and lowered boost map tommorrow. Until I get my injectors in and tuned I am going to run this boost. I think this ignition map along with the lowered boost will help solve the knock issue in the problem area. I'll report back with datalogs.

 

If anything you can run more timing because of less boost... but just wait for your injectors...

 

true, I'm going to put them in tommorow and hopefully try and have them scaled properly at least by Thursday.

Thanks!!

 

no problem... you will be able to turn up the boost as well and see if your car likes it once you have the injectors in...

 

it looks like youre going logs for 1st gear? try doing pulls in 2nd and 3rd gear and log 1 byte load instead. loadcalc for me jumps all over the place and i prefer the 1 byte. i also think that rescaling your map to fit where your car hits in the cells would help make the car run smoother.

 

To me this seems more of a fuel issue and less of a timing issue. Attached is what I would do to fix the tune in my opinion.
A few notes-
-I'd really, really, really disable lean spool. In our knock prone engines with as much boost as we run, I don't like it.
-To control knock at peak torque you should have more fuel! Don't fall into the trap of running less fuel at peak torque and running more fuel at peak rpm. It is much easier to knock at slower piston speeds and therefore more difficult to knock at higher piston speeds.
-That being said, you don't need to run as much fuel at higher rpm, especially with timing being not so aggressive. In my opinion you are probably just heating up exhaust temperatures unneccessarily.
-Timing needs to be smoother at low rpm as you enter peak torque, perhaps go full throttle sooner and redatalogg to get a better idea of your timing curve, seems a little confused at first.
-Log 1Byte Load, it is more accurate in my experience.
-I run more aggressive timing everywhere, especially up top, after the fuel curve is smoothed out and you fix your knock at peak torque, slowly add in a degree or two until you start to get 1-2 counts of knock again and then back it off. This is assuming you are tuning on 93 octane.

Again this is all opinion and I run more aggressive timing then most as we race our car and I try to extract at out all the power possible.
Dan

 

NOTE: 1 - 2 counts is NOTHING to worry bout!!!
my .02...

- turn off leanspool! via periphery. (you will have to re-tune your fuel map, tho)
- your boost map needs work. First I would rescale your rpm axis so you can utilize more of the cells. [WGDC will change too] (u dont really see bost till 2500 anyway) I set mint to start @ 2000, 2500, 3000, 3250, 3500, 3750, etc.
second, I would set up the spool up area to be linear, no 24.6, 0, 1.8, etc. U can just set it to be whatever your peak boost. ex. if ur shooting for 21psi, use 21 all the way down,to peak boost. Not quite sure why u have the 24.6's (if ur only shooting for 21), and then 0, ...
-ur timing is conservative from 120/1500 all the way down, and all the way to peak, altho if your car only likes 1* "@ peak", then thats all she got, but during spool up, u should be able to advance that area and downward, a few *'s.
-Remember smoothness of the timing map makes for a happy car (less interpolation the ecu has to do) there is an excell sheet for smoothing in the ecuflash forum! Same for fuel, just not as important as timing... I smoothed my fuel map too :P.
-U could use some timing in your cruise areas as well. 2500 - 4000 / 10 - 40 load. Log timing during cruise, and see how much advance your getting (keep in mind, the egr is adding some timing, unless u deleted it) check that map, and if its under 44*, (total) bump the timing map up till 44*. I deleted the egr, and have 44*'s in the timing map, but u most likely still have the egr active, so just keep in mind egr + timing = total timing! (during cruise)

 

A couple more thing to add to what the others have said.

First, use 1byte load or 2byte load. No one should use Calculated load.

Second, your doing these logs in 3rd gear right? Also what octane gas?

Last, dont log useless item as it slows down the logger. You dont need to log battery temp, accelenrich, coolant temp or air temp.

 

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