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Jason - you're not quite right. Under boost, the knock sensor works just fine and will cause timing to be pulled just as it would if the car were stock. if it "hears" knock, timing it yanked back. Period. The problem is that we have no factory electronic way to tune for FUEL under boost. An AFC causes incorrect load values (lower, when compensating for larger injectors), which influences timing advance to the high side, which causes the problems we have. it isn't that the stock knock sensor can't pull timing under boost, it is that the stock knock sensor can only affect timing to a certain percentage of the overall advance. When your effed up load values dictate 30* of timing advance, there is only a percentage of that which can be taken away given knock sensor input. As a NA car on 87 octane with the ECU seeing everything it can (up to atmospheric pressure from the MAP), we simply don't require much more tunability than that. So, 30* of timing advance, 15psi of boost, and 93 octane... sure, your knock sensor might scream until its hoarse, but there is only so much timing as a percentage of total advance versus load% that it'll take out.. which can leave you in a dangerous situation. It's not programmed to do more, because as these cars are stock, there is next to no way that the kind of sitation that would call for more tunability than it already provides could occur. The sitatiuon you're thinking of still occurs, but the real reasons behind it are a little different than you think.
Take it with a grain of salt.. I'm no engineer, nor am i an expert in tuning the internal combustion engine, but i've watched parameters change through my logger as i drive a lot, and i've picked up on some of the relationships between them. I understand how the system works to a degree, so i'm extrapolating operations through my emperical observations.
And anyway - i run around 15psi daily. SOmetimes more. I don't look much. My fuel system consists of 440cc/min RC injectors, a 3:1 FMU, and an SAFC. I could get more out of it, but its already made 302wHP, and 302wHP with a 3.55 final 5speed trans is fuckin scary. ______________________________ If a sentence found online has 35% misspellings or greater and includes at least two racially charged expletives, chances are it is a YouTube comment.
'95 Eclipse TurboGS (garage deco) '95 TSi AWD (restoring a survivor) '97 Talon ESi-T (poor impulse control) '99 Eclipse RS-T (daily beater) '13 Evo X (mostly stock) '17 Sienna (Middle Aged Dad Mobile)

Factory Service Manuals: http://nawdu.de/files/
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