2019 Mustang GT gen 3 Coyote - new to ECU tuning

[junits15]

Hi everyone,

I finally placed an order for an HPtuners device and I'm pretty excited to start learning how to tune my car. I had a focus ST before, I did the Cobb tuning class and got an Accestuner license but never actually tried to make my own tune. Eventually went big turbo and at that point I got too nervous to try and change anything because there was too much at stake. In general that motor had alot of control schemes going on, on top of all the regular timing control and HDFX stuff there were tons of extra tables for boost control and other things like that. It was too much for me as a first time tuner.

With the mustang I want to try and tune my own car, its a pain to have to go to a tuner every time I make a change, and with the car being NA I feel like I have a better chance at actually being successful. I've never written a tune, and I don't really know much about what goes into making a custom tune and I'm kind of nervous about breaking something. I know timing control, fueling, and knock retard are important to performance tunes, but i don't know how to change them and by how much or what order to change them in.

My goal is to start off by just making a really conservative 93 octane tune, on all stock hardware, then play with ethanol or race gas and eventually add in some simple bolt ons.

There's a lot of knowledge here, and its really great, but how did you guys learn all this stuff? How does someone new get started?

Thanks in advance
J

[engineermike]

Believe about half of what you read in these forums, do a lot of testing and logging, and beware people who use the forum to “help” by selling you a tune.

[engineermike]

Pick one topic and hammer that. You mentioned 93 tune with stock hardware. That?s simple enough. What is it that you think you can do better than the oem? Right off the bat you can add about 3-4deg timing to the borderline tables if you commit to 93. There?s a little power in OP cam timing tweaks up top, and make power enrichment come in quicker. Otherwise it?s user preference. You can do a lot of simple stuff on the transmission settings and make the pedal more responsive if you want.

[Volstang]

What engineermike said is 100% accurate.

[junits15]

Pick one topic and hammer that. You mentioned 93 tune with stock hardware. That?s simple enough. What is it that you think you can do better than the oem? Right off the bat you can add about 3-4deg timing to the borderline tables if you commit to 93. There?s a little power in OP cam timing tweaks up top, and make power enrichment come in quicker. Otherwise it?s user preference. You can do a lot of simple stuff on the transmission settings and make the pedal more responsive if you want.

Thank you for the reply,
I think this is how I'll go about it, sadly the car is manual so no transmission tweaks to be had lol. Stock tune is 87 compatible, my thought is that I can write a tune that's premium fuel only and gain a little power like that. Similar to the ford performance tune.

From there that should be a good way for me to get started before moving onto different fuels and bolt on mods. I think I'll start by watching how the stock tune behaves with 87, and 93 in the tank with some logs. Behavior with 87 should give me an idea of what ford believes is a safe "worst case" scenario so I'll know what to avoid.

I'll look into your suggestions, it sounds like the name of the game is to increase power by increasing timing wherever possible.

[engineermike]

The stock “87” tune actually advances timing until it senses knock. So you won’t ultimately find more power by adding to the borderline table becaise knock will be found at the same timing as before. But it will reach max timing sooner since knock advance takes time. That reminds me; you can switch it to per cyl advance and might pick up a little power on that.

[junits15]

oh ok, well in that case I'll see what I can do.

I'm familiar with the KOM method of changing timing with octane, but I had assumed there would be some headroom left that I could take up. The only reason I want to keep stock hardware at the beginning is to minimize the number of things that I need to change all at once.

Maybe some race gas or ethanol will be a better first move, either way thank you for all the replies!

[engineermike]

You still get better response with higher borderline, since the starting point is higher. The performance pack does just this.

The gen3 has octane learning disabled. Instead it just finds knock with the knock sensors then switches to the slow knock advance rate. I guess they figured this works better for the application. It’s switched off in the f-150 too. Also, they switch to global at high rpm so theoretically you might only get 1-2 knock events at wot.

[junits15]

You still get better response with higher borderline, since the starting point is higher. The performance pack does just this.

The gen3 has octane learning disabled. Instead it just finds knock with the knock sensors then switches to the slow knock advance rate. I guess they figured this works better for the application. It’s switched off in the f-150 too. Also, they switch to global at high rpm so theoretically you might only get 1-2 knock events at wot.

Ah i understand now

Do you mind if i ask a few more questions? You seem pretty knowledgeable and I see your name all over this forum lol.

I just got my dongle and downloaded the stock map off the car, when you say add timing to the borderline tables is that a recomendation to universally bump up the timing on all borderline tables by the same amount? (At high load and RPM only of course).

What i mean by that is that, if i wanted to add one degree at 6500 RPM full load, do I add one degree to all mapped points at that condition? I'm trying to learn what governs which table the car is actually using, from what I see I would guess that id want to only edit the tables that are appropriate to add timing to, and id also guess that some of these tables are designed for less than ideal scenarios and should be left as is.

thank you

[engineermike]

For the route you’re going, if you keep the stock method for controlling spark and commit to 91-93 octane then I would just add 3 to all borderline tables. The idea is to start it out close to knock but keep it from initially commanding something past knock. It will ride the knock sensors if it can’t reach mbt. Another strategy would be to keep it just below knock, which is what I did with mine. This takes a good bit more effort though.

[junits15]

Sounds good to me! Thanks for the help

[junits15]

hey So I want to bump this because I've actually collected some data and tried some things. I'm pretty happy because it seems like i've actually accomplished something with this car

I've tested two scenarios so far
1. flex fuel with the car at e34 all stock timing
2. regular 93 with borderline increased by 2 deg in the upper 14 MPs

If anyone wants to look i've uploaded both logs here

03_clipped_e34.hpl
07_clipped_93_oct.hpl

Here's what I find the most interesting at the following conditions:
IVO: 10 deg
EVC: 19 deg
RPM: 6100RPM
Borderline: 22.5 deg
MBT: 24.4 deg

the 93 log has a final timing of 20.5 deg, while the ethanol tune is applying 24 deg of final timing. The ethanol tune is flowing an additional 3lbs/min of air through the motor as well. Am i right in assuming that the ethanol tune with no timing adjustments is significantly outperforming my 93 tune with timing adjustments? My old rule of thumb was 10WHP per pound of airflow per minute, it doesn't seem logical that an additional 30HP could be picked up just by using ethanol. Or am i wrong? This feels too easy.

[paulsmithsr]

Got a good tune for 250. Also can teach u too

[engineermike]

Your air load is higher on the e34 due to intake air temp difference. It was much cooler.

Looks like E34 cleaned up the knock and you were riding MBT. You could probably add to your borderline tables to get closer to MBT on the initial hit.

On 93, the timing is pretty low and you are getting knock. Are you sure it's true 93?

[junits15]

Thank you for the reply!

Your air load is higher on the e34 due to intake air temp difference. It was much cooler.

That makes perfect sense to me, I did the e34 log in the dead of winter, I forgot to consider that.

Looks like E34 cleaned up the knock and you were riding MBT. You could probably add to your borderline tables to get closer to MBT on the initial hit.

I think you are right, I will be trying this soon. I'm still not 100% comfortable with just blanket adding timing like I'm doing so I'm hesitant to just keep bumping the numbers up.

On 93, the timing is pretty low and you are getting knock. Are you sure it's true 93?

You know, I'm not sure, and have no real way of knowing. I have long suspected that the fuel in my area is not truly 93, as on my previous car I always made less power than expected. I was a bit surprised at the amount of knock on 93, but I am not well versed enough yet to know what a typical level of knock is for 93.


Here is a new log I took with what I feel are very interesting results. The car rode MBT for most of the pull. This log was taken with about a half can of VP octanium added to the tank which should yield a theoretical octane of 96. I don't like using octanium because of the buildup it causes, but I was curious about it's capabilities. This is the same tune as the 93 file (designator 07_)
07_full pull_2_041523.hpl
07_octanium_timing.png
I was particularly happy with this because it rode MBT from 4k until redline. However I didn't really change much on this calibration from stock, and as you'll see most of that advance is from the KR adding timing, I think I can push the borderline a lot closer to MBT on this file. This is something that has become a bit of a stumbling point though, in order to add that much extra timing to borderline, I need to either reduce the number of MPs or do something different. Not sure yet.

[engineermike]

There are some rules of thumb like, 1 octane number will buy you about 1 deg of borderline timing and it will apply pretty much universally at various cam timings. I would be completely comfortable adding 3-4 deg (or more) of borderline at all mapped points, all loads, all rpm for a dedicated 96-100 octane tune. In fact, the frpp gen3 tune just adds 2-3 deg of borderline in most places, and they stipulate 91 octane. The CJ tune has all the borderline tables Max’d out and it just runs mbt all the time.

[junits15]

There are some rules of thumb like, 1 octane number will buy you about 1 deg of borderline timing and it will apply pretty much universally at various cam timings. I would be completely comfortable adding 3-4 deg (or more) of borderline at all mapped points, all loads, all rpm for a dedicated 96-100 octane tune. In fact, the frpp gen3 tune just adds 2-3 deg of borderline in most places, and they stipulate 91 octane. The CJ tune has all the borderline tables Max’d out and it just runs mbt all the time.

By chance do you have that FRP gen3 tune file? I've been trying to get ahold of one to look at but so far haven't been successful in finding one.

Pardon my ignorance, but what is the CJ tune?

I've added some more timing and I'm about to go and give it a rip, should be interesting for sure.
Thanks again

[engineermike]

I might could dig it out. There’s absolutely zero surprises in it though. They just did a different maf cal, tb cal, and borderline to go along with the bigger maf, bigger tb, and octane change.

CJ = cobra jet

[junits15]

I might could dig it out. There’s absolutely zero surprises in it though. They just did a different maf cal, tb cal, and borderline to go along with the bigger maf, bigger tb, and octane change.

CJ = cobra jet

Ah no worries don't go out of your way to find it, its really not that critical. I have a Bullitt file which from my understanding is very similar.