Understanding knock and ignition corrections

[Alex@Stratified]

Knock, Ignition Corrections, and detonation are things that everyone watches on their tuned cars to make sure everything is running safely. Fords knock control strategy is quite complex and very tunable. Over a year ago we wrote an article on how to interpret knock readings - but it was time to update it with clearer images and information.

Further we get asked about this daily so here it is - all the nitty gritty details about knock and ignition corrections.

 

[Ceecab705]

Great info, thanks!

 

[Zoran]

Great article!

 

[CivicAssassin]

Good stuff! Do yall have your tunes set for a max correction of +4? I only ask because my OTS COBB tune would see +6.

 

[LilPartyBox]

I will be adjusting my logging parameters tonight. I only watch ingnition correction currently. Thanks for the write up!

Sent from my SM-G930T using Tapatalk

 

[Racer83L]

Alex, thank you for the article. Something I have been wondering, I dont like keeping my AP on my dash and im too lazy to mount and take it down when I arrive at my destination all the time, if I keep an eye on it for a few tanks of fuel and all is going well safely, is it okay to stop watching it and take the AP out of the car, or is it something where something could possibly start going wrong a few thousand miles down the road..


Thanks again,

 

[Alex@Stratified]

Good stuff! Do yall have your tunes set for a max correction of +4? I only ask because my OTS COBB tune would see +6.

Yes at lower loads there is a max of 4 and at higher loads this max drops to 3 om our flash tunes. On the big turbo tunes I sometimes adjust this further depending on the fuel used and turbo setup.

Alex, thank you for the article. Something I have been wondering, I dont like keeping my AP on my dash and im too lazy to mount and take it down when I arrive at my destination all the time, if I keep an eye on it for a few tanks of fuel and all is going well safely, is it okay to stop watching it and take the AP out of the car, or is it something where something could possibly start going wrong a few thousand miles down the road..


Thanks again,

I don't think it's necessary to keep the AP plugged in all the time. If the fuel and parts on the car have not changed the tune does not change either. Taking a quick look at OAR for example ever so often is a good and fast gauge on making sure everything is still performing as it should.

 

[OffTheWall503]

I've considered having you guys do a datalog review/revision of my tune.

For the $75 for both fuel types (92 and E85) it seems like it may be worth it. Can you specify what improvements may be had from reviewing a flash tune?

 

[Alex@Stratified]

I've considered having you guys do a datalog review/revision of my tune.

For the $75 for both fuel types (92 and E85) it seems like it may be worth it. Can you specify what improvements may be had from reviewing a flash tune?

If the car shows via datalogs that there is room for added performance we add boost, timing, or both in the areas where it looks to support it. If the data shows unsafe operation on the other hand we adjust the tune to bring it within safe operating parameters.

 

[enamelizer]

Knock knock.
Who's there?
Detonation.

 

[flat_lander]

Detonation who?

Sent from my VS986 using Tapatalk

 

[enamelizer]

Detonation make engine go boom!

HAHA! Ok, I'm not funny.

 

[Alex@Stratified]

Put together another video that clarifies the distinction between knock and preignition.

[video]https://youtu.be/T7FMnwBAIJM[/video]

 

[Alex@Stratified]

Knock detection and control have been hot topics for the Ecoboost community. I put together an article to give further insight into how this all works. It's a complex system, but worth the read if you've wondered what to make of those Ignition Corrections you're monitoring via the Accessport.

http://stratifiedauto.com/blog/how-the-knock-detection-system-works-in-the-ecoboost/

 

[codestp202]

Awesome info! Have been very satisfied with my e30 tune from you guys!!

 

[shouldbeasy]

Isn't the knock correction very similar to any other piggyback system? What are the main differences between the knock correction system on the Ford compared to my supercharged Toyota?

It seems similar - perhaps it's the speed at which the corrections are done? As I can monitor knock corrections per cylinder as opposed to cylinder bank, the fact that individual cylinders can be corrected is the key?

Edit - seems like the OAR learning is 'new' and related to the multifuel capabilities of the Ecoboost engine platform - also, adding timing is key where as most only remove timing from a set value in order to obtain 'no knock' conditions. Basically there is a median value which is tuned for and using the OAR and other variables the ECM will either add or subtract timing?

 

[shouldbeasy]

Awesome info! Have been very satisfied with my e30 tune from you guys!!

And I am a blast at the parties me and my dog have.