RomRaider

Hi Guys,

I'm from Australia with an '08 WRX(MT, 5dr hatch) 2.5L.

Last dyno'd powerrun = 166.8kW @ 4 wheels, 4th gear, sea level, Ambient 32 celcius, Intake 44 degrees celcius about 5000N of torque(ish)...

Mods so far are...

* Haltech Interceptor(I have the map for it as well handy)
* Greddy Profec Spec IIB Electronic Boost Controller(55% WGDC on High boost in 4th nets around 14-15psi constant)
* Exoticspeed GT350ES Turbo(16g-ish size).
* Tactrix Openport 2.0 to log/flash.
* 3" Turbo Back Exhaust

I had the Haltech professionally tuned a little while ago, so I know that the tune is safe on 14-15psi, there isnt much work done with it at all, just some minor tweaks... (After pulling the map - can post)...

So, what I'm wondering is, do I really need to let the ECU determine the initial WGDC etc since the EBC does the job for it?(And a good one at that!) Pretty much on my saved map(not reflashed yet) I've raised the Max WGDC to 90%(because I'm controlling it with the EBC) and pretty much raised all of the Initial Boost settings to something that I would consider High? I have also raised the Maximum Boost tables as mentioned above, I will be letting the EBC take over those duties(since it has warning and peak-hold and audible warnings!)

What are peoples thoughts on how the ECU should be setup with an EBC? Or can I see your MAPs?

NOTE: I have not re-flashed the ECU as yet, I am researching and using the MY08 WRX maps as a very good guide, since the engines arent too far off(HP wise, turbo size) and I believe that the MY08 WRX & MY08 STi share the same injectors, but the STi seems to have an exhaust cam adjustment, where as the WRX only has intake(which I have changed to mirror the STi)... Is this an acceptable approach(initially?) Of course, the logging will tell me(as well as seat of the pants) if it's a good idea? I havent used the same rev-limit as the '08 STi which seems to be 8000rpm. I've only upped mine to 7000rpm(+500rpm from standard) as I remember reading an article that 500rpm is generally acceptable, but anything over that can cause undue stresses on the 'rods, and i dont know how good they are?

PS: A few times now I have run into limp mode(CEL, Traction and Cruise lights go on) whilst going up a slight incline, 3rd gear, just after the rev limiter it comes on, I assume that this is the boost limit(it looked like the stock WRX was set pretty low?) Or is this something else that I need to look into with logging?

Thanks
Matt

Any help?

to answer your question, no. The EBC's functionality takes the place of the factory setup. Your target boost, WGDC, and turbo dynamics tables will effectively be rendered useless. I'd leave the OEM solenoid in the car, and plugged in so you don't get a CEL, but place some vacuum caps over the exposed ports to keep dirt and dust out.

I'm sure you could get fancy and include the stock BCS or an aftermarket 3-port BCS, but I don't see the reason.

regarding the CEL and flashing cruise, you probably hit fuel cut. Stock ECU places it ~16 psi on your car if I remember correctly. You'll want to reflash your ECU and set a realistic fuel cut setpoint, so the engine can catch itself in the event of overboost, but the rest of the boost control duties will be relegated to the EBC.

hi ben,

thanks for your response!

I've obviously lacked detail here, which wasnt on purpose. The guys that did the tune commerically have left in the stock BCS and done what you said. I didnt realise that it was important to leave in! My bad.

The cut is what I hypothesized, because it's relatively difficult to hit that point(if I get it, I'm really, really really up it.) eg. above 135km/h in 3rd gear on an incline on a cold day(or whatever 6500rpm redline is in 3rd). he he he. On controlled roads, of course.

The stock map says the following. Boost limit - fuel cut.

15.28psi @ 2000-4000.
14.99psi @ 5000rpm.
12.57psi @ 6000rpm.

I'm not 100% sure what the trigger point is, if it's upon breach for more than x number of cycles, or if its after the RPM drops again(clutch ON)? But it only happens once I clutch in and grab 4th.

My fuel cut will be realistic in my new map(about 19psi) with supporting mods. Perhaps 20.

Just in summary, do I actually need to modify the maps(to stop any CEL issues?) or will the ECU simply ignore them?

Thanks
Matt

That is pretty common. When you shift from 3-4 aggressively, you're getting a spike as boost rises quickly, and the higher load from the taller gear is even more prone to a bit of overshoot.

you will need to adjust the fuel cut threshold in your map, and the overboost CEL threshold as well. Other than that, your EBC will control the rest. Think of it this way... your ECU controls boost as follows:

Target boost table
Initial and Max WGDC using the stock 2-port solenoid
Turbo Dynamics tables
Assorted boost target and WGDC compensation tables (IAT, altitude, etc)

The EBC will replace all of that functionality. However, if your manifold pressure rises above the fuel cut threshold, your stock ECU will still activate fuel cut. You will simply control your boost using the EBC rather than the ECU tables.

Hi Ben,

I've already prepped my new map in anticipation for the new ECUFLASH Release so that I can actually reflash the ECU, this should alleviate all of those problems. But I've taken the last few days to do logging each and every day to get an idea of where I am getting knock etc and the boost being hit.

but let's see how I go.