Did i get some bad Gas ? Decipher CoBB AP #'s

[BoostCreep]

Sounds pretty normal to me…

Was gonna say, this seems within the normal range. Just because it’s pulling some timing doesn’t mean somethings wrong, it’s designed to do that. The Garrett is a good intercooler, I wouldn’t be too worried about heat but you can’t expect it to run at full advance in non ideal conditions.

 

[1BAD454SSv2]

Still like to know why the knock octane modifier switched one day to next. Still on same tank of fuel i filled up with last week . i will be topping off at my regular station today . I am going to switch to 91 stage 1 OTS today . One thing about crappy hot air, is even worse on N/A engines. Thanks for the help.

 

[BoostCreep]

Hot air is definitely much worse on a high boost turbo motor than an n/a motor. It’s the opposite as far as altitude is concerned.

 

[TwizzleStix]

Still like to know why the knock octane modifier switched one day to next. Still on same tank of fuel i filled up with last week . i will be topping off at my regular station today . I am going to switch to 91 stage 1 OTS today . One thing about crappy hot air, is even worse on N/A engines. Thanks for the help.

I haven’t observed or logged KOM at startup because I just don’t feel the need. I did read that the KOM is held at -1.0 at cold start until the engine temp comes up. There is a whole lot of functional description in the Cobb Accesstuner support files on their web site. Maybe I’ll take a look at mine to see it. I’ve seen people freak out while watching AFR at startup as well and see anomalies as the O2 sensor heaters come on and fluctuate. I recommend not watching any real-time data at initial cold startup!

 

[1BAD454SSv2]

I filled up my regular gas station and switched to 91 Stage 1 map . I give about 15 -20 miles before WOT so far 3/4 throttle it was adding 4 deg of timing and only saw .50 neg . It was 102 deg with A/C on as well . Interested to see how much timing it will pull next month I'm sure there will be some 122 deg days like in 2020.

 

[1BAD454SSv2]

This is after racing a coworkers's Genesis g90 , one that looks like a Aston Martin . I steadily pulled on him till 90. Stage 1 feels stronger to me. Maybe not enough octane to take full advantage of stage 2. Pic took right after racing 65 deg out .

 

[1BAD454SSv2]

Playing around with 5 gallons e85 added to 91 octane 26 gallon tank. Looks like its adding 5 deg of timing now. Correct? Feels better still running stage 1 ots tune. 110 ambiant and humidity is up.

 

[TwizzleStix]

FYI, that “highest” timing parameter is the sum of each added (or subtracted) timing value, not a single max value.

As the engine operates, the ECU always adds timing in specific amounts, around 1 deg, until it gets a tiny knock event, then subtracts a specific amount to stop it. These specific amounts, added and/or subtracted, are set in the tune and the flash-tuning software I’ve used makes them available for the tuner to adjust.

So, more info than you asked, but I felt I should explain the data monitor just a bit because it isn’t obvious. Well, it wasn’t obvious to me when I first used it.

Anyway(!) your answer is “yes”, the E85 mix added more timing than your “normal” fuel.

If you also take a look at the LTFT you will see it is adding fuel to hit the AFR target. If it is more than say +10%, then you might want to add some gasoline. Goose can set you up with a tune for just about any amount of E85 you want to run. These EcoBoost engines will make significantly more power running the corn whiskey!

 

[1BAD454SSv2]

I will check that tomorrow. Long term fuel trims . It mixes out to e27. But heard this station is tad low on percent. My coworker says it tests to 65% alcohol. He runs it in his zl1.

 

[1BAD454SSv2]

FYI, that “highest” timing parameter is the sum of each added (or subtracted) timing value, not a single max value.

As the engine operates, the ECU always adds timing in specific amounts, around 1 deg, until it gets a tiny knock event, then subtracts a specific amount to stop it. These specific amounts, added and/or subtracted, are set in the tune and the flash-tuning software I’ve used makes them available for the tuner to adjust.

So, more info than you asked, but I felt I should explain the data monitor just a bit because it isn’t obvious. Well, it wasn’t obvious to me when I first used it.

Anyway(!) your answer is “yes”, the E85 mix added more timing than your “normal” fuel.

If you also take a look at the LTFT you will see it is adding fuel to hit the AFR target. If it is more than say +10%, then you might want to add some gasoline. Goose can set you up with a tune for just about any amount of E85 you want to run. These EcoBoost engines will make significantly more power running the corn whiskey!

Thanks for the info.