I'm running 17 psi right now which is pushing 300 cfm..the limits of the stock MAF on my car. I'm still working on that. Running Cobb Accessport and I think the solution is just to lie to the computer about your target A/F ratio above the 300cfm limit. Maybe someone more familiar with subaru tuning can chime in on that.
Sell the Accessport and buy a Tactrix cable. Download the freeware software you need (ECUFlash and ROM Raider).
You have a couple of solutions, I'm going to list them by order of preference... keep in mind I've only done AEM on built engines and ECUFlash/ROM Raider on stock ones. I can give you very good advice, but if you aren't sure when I'm speaking from experience and when I'm playing with ideas PLEASE ASK because I don't want to fuck you on the deal.
1a) Subaru is one of the best MAF implementations ever, but to do anything with what you have and keeping the MAF is going to cost money. See if there's a speed density hack for your ECU (I know there is for 04-ish STi, and I *think* bugeye) and milk that.
1b) Blowthru MAF skews what the MAF actually reads, lower's it's ceiling so to speak. Dropping that sensor into a 70-75mm housing pre-turbo will both not skew it's output as airmass goes up, but also increase it's peak. Hell, you can probably try for a full 80mm housing as that's the size of your turbo inlet BUT be aware that when you make a MAF too large you can kill off it's ability to read airmass with any resolution at idle.
* keep in mind that 1a and 1b are ASSuming that a built motor with excess clearances aren't wreaking havok with the knock sensor, which is a backbone sensor in those ECUs. Unlike Evo you can disable it and tune off the base timing map, but I really recommend dyno time. If the KS is freaking out I'd do that with my own car, but you might want to look into buying a $400-500 Honda AEM and wiring it into your WRX. *2) Diablosports MAFia to rescale your MAF in it's current configuration. $180 new I think? The basic idea is that hotwire MAF are 0-12 volt devices, but the ECU can't read past 5 volts of that signal. A MAFia will compress 0-6 volts into 0-5 volts, etc, increasing what you can read out of the meter right up until you lose resolution at idle exactly like having too big of a MAF housing.
3) Honda AEM wired into a stock WRX ECU plug. If you are feeling snappy, and want to keep scantool emissions, you can keep the stock ECU powered w/ all codes disabled and the force readiness box checked and let it pick up OBD2port duty.
I'd be curious to see some datalogs, with an eye to AFR, timing, IAM, and KS feedback. Also, it sounds like you're pretty bright/decently well read on the cars to get what's obviously a 300 whp 350 wtq Scoob to hold together, but please don't raise the revlimit or you'll shit the oil pump.
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Topic: 02 WRX HY-35 (Read 29513 times)