RomRaider

2008 USDM Legacy GT, 5EAT
EJ20X longblock, with avcs delete kit (stock cam, but modified with a delete kit)
93 octane
2008 LGT upper/tgvs/rails/injectors/intercooler etc. everything above the heads is OEM/USDM
VF52 with wastegate port entry and exit ported, VF52 restrictor pill, stock BCS
*stock turbo back exhaust
2014 WRX Intake
Air pump delete, baro sensor from top of pump intact

so a basic "stage 2" (downpipe) and full tune.

the only problem we've had so far is that it's not reaching target boost, which is ~15 psi. I worked up the wastegate duty until I felt it was not being realistic, and then upped the boost controller frequency to 20hz, and worked up from near the bottom again. and at 74 to 80% duty, it's only getting 13.5 to 12ish psi of boost, give or take

either the wastegate flapper now sees much more exhaust gas pressure and is easier to open, and the boost controller cannot vent enough flow to decrease pressure against the wastegate actuator, or the stock exhaust cat-back with 220,000 miles is clogged and limiting to 170 to 200 g/s range

note that from 2008 to 2014, the same engine bay fuel system setup was used on the LGT and WRX, and that the 2014 WRX was the most updated per cylinder injector compensations in an OEM calibration, which I used in this. that's how I know. I looked at the fuel trim corrections early on when using the OEM per cylinder injector comps, and looked at the 2014 WRX OEM tables, and figured it out. I went online and found the OEM injector feed parts and compared them visually. same/same.

cruise (tgv closed) avcs and timing are modeled from OEM 2014 WRX, with correction for displacement and compression ratio difference

off-cruise (tgv open) avcs and timing are modeled after a 2007 STi which I tuned extensively, and is corrected for displacement and compression ratio difference

I have another sort of example I'm working on, but haven't gotten any logs back from the owner and he's got some sort of problem with his upstream as he's getting a P014E code. it's an ej20x in a 2012 STi, with the exhaust avcs being utilized. it's using the same cruise avcs and timing, with 0 commanded exhaust avcs as here, but then the intake/exhaust avcs + timing are derived from the 2011 JDM S206 (aggressive overlap) for TGV open, compensated for compression ratio difference of course. I guess it drives fantastic, but I was hoping for datalogs. He didn't seem compelled to message me at all until a couple days after I messaged him about 10 days after it was flashed. success, I guess?

in any case, if you want to take your OEM calibration and modify it for a different displacement and/or compression ratio, use boyle's law for correction factors against avcs and timing airmass axis. huzzah.

if it's general consensus that the dash/logged parameter for (mpg est.) is about 10% off, then 38 to 40 mpg average is still 34 to 35 mpg.

we'll eventually figure out the boost control problem, but the rest of the tables are good, so pay no mind to copying wastegate duty/target boost. DBW tables IIRC are from a 2008 STi.

images from datalog

back onto the exhaust avcs,

from reading the input of more experienced engine rebuilders, these motors are supposed to have a pin that locks centerline on the exhaust cam when the exhaust avcs solenoid is unplugged.

despite this, I felt something was off in the very first go, and recommended doing an avcs delete on the exhaust cam. he used a kit from somewhere, and modified the oem ej20x camshafts when he ported the vf52 turbine housing for the wastegate entry and exit.

according to the pros, this is completely unnecessary. the exhaust cams supposedly do not have any incorrect centerline alignment when the solenoids are disconnected, without modification.

I added more avcs to off cruise, added more timing to off-cruise, adjusted injector timing again for the greater avcs, and was able to get some more data.

unfortunately, it still has a boost control problem. I had thought it was with a Cobb DP, but turns out it's all oem behind the turbo. I'm betting it's clogged.

we're swapping the boost controller but new exhaust parts are on the way.