Quote:
Originally Posted by biz77
Meaning it can determine the severity of a knock event?
By “overreacting,” do you mean responding exactly as intended by the BMW engineers based on a serious knock event?
Mike, again:
Here is an explanation on the Subaru knock control system: http://www.romraider.com/forum/viewt...hp?f=25&t=1840
How does BMW’s system differ? I can go and set my timing tables on my Subaru so that it also knocks on pump gas (not that I would.) The knock control system will circumvent the knock through feedback knock correction, fine learning knock correction and IAM adjustment. If I put race gas in, the system will then advance timing back up in response to the higher octane. Again, how is this different from what BMW is doing? |
+1
This is exactly what I've been trying to convey to Mike for a while now... these timing features/fundamentals are spread across a large number of platforms.
Quote:
Originally Posted by Sniz
we may have just witnessed the beginning of JB subi, a branch of JB bmw
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I try not to post anything incendiary if possible (unless I'm in an OT section
) but I couldn't help but laugh my ass off at that one haha!
Quote:
Originally Posted by Clap135
lmao YEA RIGHT, a subi wouldn't make it out of 2nd gear running a juice box.
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^^^LMAO!! Debatable... it might make it to 3rd gear (depending on 5MT vs 6MT ratios)
On a somewhat related note, I actually stumbled across an old thread Shiv made about ignition correction/timing control a while back. Man, he pointed it out, clear as day, but still no concession... I won't lie, I have a pretty high tolerance for not getting worked up in a debate, but Shiv has my sympathy for sure, that must have been frustrating. Good read though:
http://www.e90post.com/forums/showthread.php?t=282443
I especially like a couple small clips from that thread. One from a man with a strong understanding of how timing works:
Quote:
Originally Posted by shiv@vishnu
In this post, I'm going to explain how the factory Timing/knock control system works. It's no different, in concept, to any modern engine control system (Mitsu, Porsche, Subaru, etc,.) Most of the differences between the different ECU types has to do with response times, adaption logic, etc,....
Shiv
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And another small quote that I almost died laughing from:
http://www.e90post.com/forums/showpo...5&postcount=62
Quote:
Originally Posted by Mike@N54Tuning.com
It gets to be a complicated detail oriented topic. For example, it is well understood and agreed by most that there is a ceiling to how much timing the ECU will add. The ECU will add timing up to its "knock threshold" OR that ceiling, whichever is lowest. It is not well known or understood how that ceiling is determined. Octane adaption is a major contributor and the principle method through which the CPS offsets are learned out. And a major contributor to total timing advance, much more so than IAT....
Mike
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Apparently he didn't realize these cars have timing tables (aka "that ceiling") haha... like just pretty much every other modern performance car out there.
Sorry, this was really unnecessary, but I really couldn't help myself on this one.
-Brandon