WRX 04 PPP spool/lag/boost treshold
 

To all WRX PPP owners (ej205 with stock PPP map): how much lag/boost treshold do you have? I run PPP ecu on my WRX and boost treshold seems to be quite high to me - it's all subjective, but engine seems to be quite alive only past 3500-4000rpm. Below 2500rpm there is nothing here, around 3000 it starts pumping. I have a boost gauge and I think that on 3rd gear it reaches 1bar about 3500rpm (on 5th gear about 3100-3200rpm).
Could you tell me how it looks in your PPP WRXes? Please include information on which gear do you measure it (preferred read from 3rd gear) and include info about any other performance mods.
It could be a read from your gauge or preferably a log from romraider.
Cheers

PPP maps should be targetting just shy of 1.3 bar boost - the main pull comes around 2800-3100rpm - can't find any logs handy at the moment but yours sounds a little down on boost. Might be worth getting it plugged in to see if the IAM has dropped.

Is it just the PPP ecu your running not the silicone turbo/intercooler pipe as well? The silicone pipe will make a difference over the standard hard plastic one.

2800-3100 at which gear? 3rd?
IAM is ok, I checked it mant times, and it always had max value (16 if I remember correct).
I have both ecu and blue y-pipe.

yes 3rd gear closer to 3100 end and 4th gear closer to the 2800 end. Adjusting the wastegate arm can help here.

If your logging with romraider, check your WGDC current vs MAX and also boost error or manifold relative pressure direct vs target boost (psi relative).

Some time has passed and I think I still have quite late spool up on my WRX PPP. Things checked/done in the meantime:
- found a leak on the uppipe's gasket - new gasket and catless uppipe have been mounted (so I also can eliminate a clogged precat);
- changed multiple hoses (PVC etc.) under inlet manifold and main turbo intake pipe (new OEM) - while changing leaking fuel hose;
- rebuilt long engine;
- pressure tested intake by a shop, no leaks found;
After these operations I don't feel too much difference to how it felt earlier. Especially leak on the uppipe gasket was very loud, so I thought it would make a difference.

The one thing that I have left to do now is to replace GFB BOV with a stock DV. After that I will do the logging.
Do you have any ideas what else can cause late spool (when it reaches 1.25bar it stays there, no fluctuations, etc.)? Do you think that tightening wastegate arm can aid spool up?

i would log first and compare target boost to actual boost - might have saved you throwing some parts at the car you didn't need? Tightening the arm can help spool up, assuming that it's hindering spool up now, could also be missing/incorrect restrictor pill in the turbo vac lines OR simply the ECU is happy with the amount of boost your making (the logs will show this).

The problem is my OBD port refuses to cooperate. The cable gets powered but cannot communicate. Last time carb cleaner helped a bit, but this time I cannot communicate with my ecu. The cable gets power, but it struggles to communicate. Any ideas?

Firstly I tihgtened a spring in my BOV and it helped a bit in gas pedal reaction (but not in spool times). After that I swapped the BOV for a stock DV. I felt no difference whatsoever.
Apart from that I noticed one thing - while driving along crash barriers when I press full throttle I can hear sound of leaking air from outside (similiar to what had before with blown uppipe gasket, but not as loud). So I see following options here:
- Intake leak - but the shop claims that they have pressurised the intake and didn't find any leaks.
- Pre-turbo exhaust leak - but I have just cured one major leak here - the uppipe and its gaskets have been replaced recently. Uppipe was visually checked before mounting it. I think that engine gasket set also contains manifold-to-head (inlet and exhaust) gaskets, so they are also new. So only either shop mistake or exhaust manifold gaskets are possible here, right?
- Wastegate too loose? Could too loose wastegate actuator give this kind of sound (leaking air under pressure)? On the other hand, under high load wastegates gets opened to release too much gasses, so it should give similar sound everytime you have low WGDC for example above 5000rpm with full throttle, am I right?

OK so have the shop pressure test for leaks again, check the intake and check the exhaust with pressure/smoke to determine if there is gas escaping anywhere that would be hurting performance.

If you could talk to the ECU you could check the fuel trims (a/f correction A/B/C/D values) which would also help narrow down any possible leaks. The ECU has so much control over things your really just guessing at a solution without being able to get data from it.

I had a similar issue and I found that one of the wires that lead from the OBD socket had lost it's insulation. So applied some electrical tape and all was good again. The wires are very thin and are bent over at a tight angle. So it's quite easy for them to suffer damage (breaks/shorts) etc over time, with people pushing and pulling on the OBD socket or even just undoing the lower trim and stretching the wires that way.

How to pressure test exhaust?

I have to wedge a piece of cardboard behind whatever is plugged into my obd port to get it to work, try holding your reader at strange angles and see if you get a connection