RomRaider

Hello everybody!

I'm new to the open source ECU tuning community. But Im eager to learn and hopefully start tuning my Subaru.

I have looked through the supported ECU's but don't think mine is compatible. I've attached a picture of my ECU for a 02 Impreza WRX USDM manual.

The code didn't match anything on the list so I'd though I'd ask the community if they had any insight on whether I'm compatible.

I believe that ECU willl be running A4SGC00C - should be flashable no problems.

Thanks! I came across a openport 2.0 on craigslist today. Was able to ream the ROM using ecuflash.

Words of advice. Check the USB cable. Turned out to be using either a bad cable or charge only USB. Also don't forget to connect the green plugs under your drive dash so it can go into testing mode for ROM read

A4SGD10C 1B14400605

I have a theoretical question about boost. I am very new to turbos and open source tuning. But I hope my question doesn't sour too many people because of my lack luster knowledge.

Target:

Create the least amount of boost possible by wastegate duty cycle percentage.

Theory:

Max Wastegate Duty Cycle set to 0% across all RPM/throttle percentage values in table

Initial Waste Gate Duty to 0% across all RPM values

Target Boost to "what ever the natural/mechanical dynamics of created boost of this turbo in psi" across all RPM/throttle percentage values in table.

It is to my understanding that if the wastegate actuator opens fully to bleed out exhaust, it in essence is bypassing the majority of exhaust pressure away from the turbine. Where when it's fully shut those forces have no were to go and build up pressure until it reaches the turbo and starts spooling faster and faster.

My understanding for Duty Cycle Percentage of a Wastegate; ~0% duty cycle is open and ~100% duty cycle is closed.

Am I on the right track here?

yeh that's it when the wastegate is shut gasses are force to spin the turbine wheel. The wastegate duty controls how much pressure is bled off the wastegate spring and that reduces the forces wanting to push it open. The higher the duty % - the higher your boost will be.

Great, I'm relieved to know that I'm not getting somewhere with this.

Now if I were to apply this to an actual tune, I wonder how I could safely do this.

If I keep the target boost tables all the same (stock) won't the Max Wastegate Duty Cycle set to 0% prevent the passage from closing in all circumstances; thus allowing exhaust pressure to bypass the turbine; effectively only creating mechanical boost of the wastegate housing? If so, do I need to adjust anything else besides the Initial Waste Gate to 0%?

I wan't this right if I'm actually going to give it a test.

if you set the min/max wastegate duty to zero then yes you'll only see wastegate pressure. in practice its better to keep the min/max values reasonably close (I normally stay within 10 of each other) so that turbo dynamics can quickly move you from the min value to the max value.

I have just tuned to 0% across Max and Initial Wastegate Duty Cycle tables. Had some issues with the "programming voltage out of range issue". Reading out 4.2V. Solution was to run the car a bit to get over 12V. Drove for about 10 min and immediately plugged in green connectors and shorted white plug. The ecuflash log read 12.19v and flashed successfully.

I'm about to drive it and do some datalogging.

Update: I just drove 40 miles from work to home. No issues in terms of the driving experience. Then replaced my oil since it was due. Ran out a again and logged a 2000RPM 2nd gear pull to redline. I figured it would be fine since there's not much in the way of boost. It maxed out at ~7psi just as it was supposed too and the Wastegate Duty Cycle % was relative to 0%.

In terms of knock sensor datalogging, should Fine Learning, Feedback knock or Knock Correction be what I should look at? Do I need to add or remove more for the next run?

yes feedback and fine learning knock correction should both be logged to see whats going on. Take a read through all the articles posted up - that should get you up and running fairly quickly:
http://www.romraider.com/RomRaider/Articles

Some of them aren't finished yet but there is enough in there to answer your questions along with some that you've not thought of yet