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Discussion Starter #1
I installed my AP this afternoon with a base map provided by the Tuner. Uploaded the map, checked for leaks and took it around the block causally ensuring nothing arose. Which thankfully nothing did.

My question with this being a base map are there any numbers that should immediately grab my attention while driving to my tune appointment? Obviously I am not going to be driving like a bank robber to this place just a causal drive (60miles).
I just want to make sure while enroute that if something comes up on my AP that I address it before it becomes an issue.
Thanks in advance!
 

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We don't know your model/year car or what modifications the car has.

That said, there's nothing that YOU are going to be able to do if something "arises." Base maps are typically set with zeroed wastegate tables (no boost), conservative timing, and conservative fueling tables. It will very likely be "just fine."
 

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If you’re familiar with what fields to monitor and how to read them then what I’m about to say is going to be irrelevant. But for those who are less familiar this may be helpful.

The gauges I watch most closely are DAM, Feedback knock, and Coolant temp. There are a ton of other things you can monitor as well but for me this the base line to make sure my engine is functioning as it should be.

Feedback knock is an active readout of exactly what it sounds like it is. When you get knock, it will appear as a positive or negative number depending on if it occurs before or after normal detonation. For the newer models 3-5 is moderate knock and higher than 5 is severe I believe. I never get more than -1.41 which is a big joke among the Subie community.

DAM is your dynamic advanced multiplier. This is closely related to feedback knock because when you start seeing moderate to severe knock, your DAM will drop and your engine will pull timing. Contrary to what most people think seeing a very low DAM reading isn’t that terrible in the short term because your engine is picking up knock and the ecu is adjusting to mitigate that knock. This is only a problem if you have consistently low numbers over a long period of time.

I monitor coolant temp on my access port and oil temp on my Subie dashboard to because it helps you become familiar with the normal operating temperatures of your car throughout the seasons. If you see a high spike in temperature you can assume something probably isn’t right, especially when driving normally. My standard op temp in my 2015 WRX is 205 oil and 190 coolant. As the season is changing my daily oil temp is dropping closer to 199 and my coolant temp has pretty much stayed the same.

Hopefully you find this info useful, if not then hopefully someone else does. Prior to getting my car pro-tuned I had to learn a lot about the access port because I was getting severe knock.
 

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Super Modulator
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FLKC is more important to consider than FBKC.
 

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Super Modulator
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For my knowledge can you expand on that?
Feedback knock is transient knock that does not repeat in the same load cells. It's still predet and can be damaging, but really there's nothing you can do to prevent and this monitor doesn't tell you very much besides being reactive.

Knock that repeats in the same load cells is learned as FLKC. This may be due to overly-advanced timing, fueling concerns, or improper comps.

IAM/DAM is the general octane strategy meant to remove global timing when knock is seen throughout the rev-band (read: poor octane fuel). Vac leaks and oil dilution also can reduce the dynamic advance modifer.

FBKC around -2.80 is absolutely normal. Many of these result from knock-sum events that are false -- the knock sensor is band-pass acoustic and can occasionally pick up other sounds. FBKC events that are pulling more than 6 degrees may indicate some transient problem like a bad injector or electrical connection, but this is very rare. FLKC is typically more indicative of a chronic problem. Make sense?
 

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I will also add that the duty of the FLKC is also to advance timing BACK in certain load cells when the DAM is retarded.

BTW, this is also based on my knowledge of the Bosch/EJ tuning strategy. I have no experience with the modern FA20 tuning strategy.

EDIT: All I've said is based on small tweaks on a base map. FBKC can present itself when charge temp is too high -- if the intercooler is not able to keep up OR the turbo is pushed out of its efficiency range. With compressor maps available for most aftermarket turbos, that should never be an issue.
 

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Feedback knock is transient knock that does not repeat in the same load cells. It's still predet and can be damaging, but really there's nothing you can do to prevent and this monitor doesn't tell you very much besides being reactive.

Knock that repeats in the same load cells is learned as FLKC. This may be due to overly-advanced timing, fueling concerns, or improper comps.

IAM/DAM is the general octane strategy meant to remove global timing when knock is seen throughout the rev-band (read: poor octane fuel). Vac leaks and oil dilution also can reduce the dynamic advance modifer.

FBKC around -2.80 is absolutely normal. Many of these result from knock-sum events that are false -- the knock sensor is band-pass acoustic and can occasionally pick up other sounds. FBKC events that are pulling more than 6 degrees may indicate some transient problem like a bad injector or electrical connection, but this is very rare. FLKC is typically more indicative of a chronic problem. Make sense?
Yes, thank you for the thorough response!
 
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