Street Tune WOT Pull Check?

2012+ US/Canadian Civic Si / 2013+ ILX
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getsomepiggy
Posts: 4
Joined: Thu Jun 10, 2021 9:23 am

Street Tune WOT Pull Check?

Post by getsomepiggy »

Hi,

I have a 2013 Civic Si with a custom 3" short ram intake with velocity stack (sits behind headlight with a cool air duct), 2nd cat delete, and stock exhaust. I've street tuned (mainly just fuel and VTC settings) the car based off of the Hondata MAF reflash and I am pretty happy with how the car drives and performs. However, I notice that cylinder 3 seems to pick up 1-2 knocks around 5.5k rpms every time I do a 3rd gear WOT pull from 2k rpms - redline. The knock seems to only show up on cylinder 3, which I understand could be ghost knock due to the position of the knock sensor relative to cylinder #3.

Could any please take a look at my attached datalog and tune and see if anything needs tweaking? 3rd gear WOT pulls are at 2:27 and 6:05 marks.

Thanks!
Attachments
Hondata Reflash MAP v13 (injector cut edit 2).fpcal
(21.21 KiB) Downloaded 86 times
datalog0025.fpdl
(1.56 MiB) Downloaded 84 times
getsomepiggy
Posts: 4
Joined: Thu Jun 10, 2021 9:23 am

Re: Street Tune WOT Pull Check?

Post by getsomepiggy »

Sorry, meant to say MAP reflash not MAF reflash.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Street Tune WOT Pull Check?

Post by EFICU »

In regard to ignition, I'm guessing you run 91 octane? If so, there is way too much timing in the area of knock you're seeing. At your area of knock, you have 22* in the table, and the ECU is pulling 5-7* to deliver 17* at that point to avoid knock and it's still knocking. Verify your octane rating for me, and also, your intake temps are 77*f in this datalog, is it cool where you live today?
getsomepiggy
Posts: 4
Joined: Thu Jun 10, 2021 9:23 am

Re: Street Tune WOT Pull Check?

Post by getsomepiggy »

Hi,

Yes, I am in California and running 91 octane. I see what you are saying about ignition values being pulled back compared to the values in the ignition tables. Is that the knock tables at work?

The outside ambient temperature when I recorded the datalog was in the low 80’s degrees. I usually see IATs ~5 degrees above ambient temperature when the car is moving (due to the cool air duct), but the car does heat soak a little at idle and in traffic.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Street Tune WOT Pull Check?

Post by EFICU »

I see, yeah the ignition tables are too much for 91 octane, I have had cars that need down in the 14* range where your car knocks to avoid knock. Which seeing how yours knock at 17*, it might be the same thing. You said you're happy with how the car drives otherwise? Looking through the tune I see you've made a lot of changes to different tables. Not sure what all you want help with so I don't want to overstep my bounds.

What I would suggest, since you're able to keep cooler intake temps, you need to datalog the car while your temps are in the 80* range like you are, but you need to bypass the knock control so that the ECU will deliver the ignition in your tables without interference from the ECU. Once it delivers the ignition in the tables, wherever you get knock you know it is doing so without interference from the computer. With the knock control on, the ECU will always be pulling timing to avoid knock proactively where it thinks knock may occur. If your intake temps were 100* or more I wouldn't recommend it because IAT compensation and stuff come into play. So if you can datalog at night when it's cool, somewhere where you can keep the intake temps around 80* give or take while moving, that would be the ideal time to tune your ignition. Once you've tuned the ignition with knock control bypassed, then you turn it back on and the ECU can protect the engine in the future. Some tuners leave it off completely, I like to keep it on in case you get bad fuel, or stuck with 87. The way things are going, who knows what we'll have soon here in California. Are you NorCal or SoCal?
getsomepiggy
Posts: 4
Joined: Thu Jun 10, 2021 9:23 am

Re: Street Tune WOT Pull Check?

Post by getsomepiggy »

This is a super helpful explanation, I really appreciate it. Now that I have an idea what my ignition values should be around, I can confidently make changes without fear and test what works.

I understand your explanation for bypassing knock control for tuning ignition as well. I’ve read about all this online in the past but it has never been clearly explained as you just did. I’ll try to do this tonight when it cools down and see what happens.

Regarding the other tables that I’ve messed with, I welcome any criticisms/comments that you may have. I think I have a pretty solid understanding on tuning fuel, but I am not too sure on VTC since I do not have access to a dyno to be able to measure the results of VTC changes.

I am in SoCal!
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Street Tune WOT Pull Check?

Post by EFICU »

Yeah if you're comfortable making the ignition changes, when you get ready to make a datalog, make a file with the k control bypassed and take it out for a drive while the IAT's are around 80* ish. Be sure to get ready to pull over and make changes, so log with your laptop open, once you bypass the k control you may get a lot of knock quickly because the k control is no longer the commanding knock retard like it was before. Therefore, it might knock a lot right away. I would probably recommend pulling some timing out of the table before you even head out, but that's up to you.

Honestly what I would highly recommend, since you're interested in the process, you should lock the cam angle map on 0* for the low and high cam and work to tune each cam angle individually. When you tune all of them at once, there is no way to really build out the tables completely, therefore you really cannot accurately determine cam angle mapping. If you lock on the 0* cam angle, tune it, then the 15*, etc, you can build accurate data sets. You can chase a lot of things when you tune it how you are, going angle by angle you can do it right. Hopefully I don't sound like a jerk, just saying, going angle by angle one at a time is a process you will enjoy and you will get a better hang of how it works.

Are you wanting vtec to come on at 5000 rpm no matter what? Is that an rpm you want, or you felt that was best? That is another benefit of tuning each cam angle, you can find the ideal vtec crossover rpm when looking at the fuel tables. The fuel tables give you similar feedback to a dyno readout. Once you've tuned each cam angle, you can look over the fuel tables and make accurate predictions for vtec engagement rpm and cam angle mapping. Granted if you like vtec at 5000, then that is all that matters, personal preference and feel overrides what the tables say IMO.

If you need help locking cam angles or how to bypass knock control for tuning let me know. I really think cam angle locking is your best step moving forward.
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