ign corrections stock map [log]

[ihasnostang]

I've been seeing a lot of negative ignition corrections on this tank of gas while on cobb stage 2 OTS even after putting a full bottle of octane booster into a half tank of 93 . Also before booster i hadnt been seeing it peak at +8 deg correction. i went back to stage 0 today before doing two logs. i went thru and applied a color filter to areas of negative corrections. I know tunes push the engine to being close to knock, but how many knock counts should i become concerned about?

stage 0:
https://docs.google.com/spreadsheets/d/1Bqw0nT8Rh8AntLwMFYxfX2E_psQXOHbR/edit?usp=sharing&ouid=102372025983574247740&rtpof=true&sd=true

stage 2 (same tank)
:

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[Coyote Chase]

I had a similar experience. Instead of using an octane booster, I added 2.5 gallons of flex fuel to a 1/2 tank of 93 octane.
But, since you have already added an octane booster, I'm not sure what to advise... Have you considered, topping your tank off with 93 octane from another station?

 

[ihasnostang]

incase there was an issue with the log. note i am on a older version map where the knock octane modifier low is 0 and high is 1

 

[ihasnostang]

here's another one on the stock map, this time with misfire count. ironically this is the first tank of 93 after running two tanks with some e85 blended in. there are some huge negative corrections here. interesting that on the previous log the KOM was 0.250 and now it is at 0.850. i still have about 1/4 tank left

 

[Coyote Chase]

here's another one on the stock map, this time with misfire count. ironically this is the first tank of 93 after running two tanks with some e85 blended in. there are some huge negative corrections here. interesting that on the previous log the KOM was 0.250 and now it is at 0.850. i still have about 1/4 tank left

I'm having problems reading your chart. But are you running rich, or is your motor being starved for air?

 

[TeeLew]

I'm having problems reading your chart. But are you running rich, or is your motor being starved for air?

That's better than mine was stock. My car (HPP) went to 8.9:1 AFR at WOT, which is ridiculous.

 

[Coyote Chase]

That's better than mine was stock. My car (HPP) went to 8.9:1 AFR at WOT, which is ridiculous.

That's not a totally bad thing... more fuel means more cooling in the combustion chamber, but less air also means less horsepower...!??
Will your motor lean out as your rpm increases and your boost builds?

 

[TeeLew]

That's not a totally bad thing... more fuel means more cooling in the combustion chamber, but less air also means less horsepower...!??
Will your motor lean out as your rpm increases and your boost builds?

It's totally a bad thing. If you've produced an engine which you feel it's necessary to run raw fuel though during normal operation, then you've done a shit job.

Before any addition of boost or timing, my tuner just got the A/F mixture in the ballpark. That alone was a pronounced gain. I can tell the difference from the stock tune even at idle because it runs so much better & smoother, now.

 

[TeeLew]

... And on your second point, it was getting richer as the RPM increased.

 

[ihasnostang]

cobb is looking at my logs, in the mean time i switched back from the iridiums to stock plugs with no gain. this is about 300 miles?

 

[Coyote Chase]

It's totally a bad thing. If you've produced an engine which you feel it's necessary to run raw fuel though during normal operation, then you've done a shit job.

Before any addition of boost or timing, my tuner just got the A/F mixture in the ballpark. That alone was a pronounced gain. I can tell the difference from the stock tune even at idle because it runs so much better & smoother, now.

WOT is probably not considered normal operation by the manufacturer and (when needed) cooling the combustion chamber is probably considered more important than power.
"My comments are based on theory, not facts!"

 

[TeeLew]

WOT is probably not considered normal operation by the manufacturer and (when needed) cooling the combustion chamber is probably considered more important than power.
"My comments are based on theory, not facts!"

Even this type of nonsense suggests sh!tty engineering. The tuner controls the throttle. If they can't tune the engine to run under certain conditions, then change the conditions so it actually can operate. There is NO condition where an 8.9:1 air/fuel ratio is favorable in a gasoline engine, but that's what the stock HPP does on a dyno at WOT. There is no acceptable justification for this, it's just sh!t work by the engineering department. We don't need to sugar coat it.

 

[K4fxd]

.64 lambda??

Is that stock or tuned?

 

[TeeLew]

.64 lambda??

Is that stock or tuned?

Bone stock on Mobil 91 and using a tailpipe gas analyzer (so high accuracy/precision).

 

[K4fxd]

I wonder if it is in cat protection?

I'll have to look at a few eco boost tunes.

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