RomRaider

I was messing around at 1 bar boost for sometime with my EDM forester upgraded with TD04 and STi intercooler esperimenting with various setting and now wants to "turn up" the boost a little.

However, to my surprise, after increasing the target boost to about 1.2 and WGDC to about 10% more at about 75% (was around 65%), my maximum boost hardly increase. Any advice? Should I just continue to increase it further to say 85%?

Is there any formula for WGDC? I thought it would be be directly propostional to the Boost. Is it linear?

It really varies on many factors, primarily your wastegate arm tension and your tune. Remember the table you are adjusting is MAX wastegate duty cycle. The ECU will try to adjust using the turbo dynamic tables up to the max WGDC. You may want to try and adjust your WG arm a few turns to see if you can hit your target easier.

I had to tighten mine ~6 turns and run max 95% WGDC to hit my target of 18psi.

OK! Thanks for the heads up! Will try. BTW, do you need to remove anything to tighten the arm?

I suspect that since my stock Forester runs a stock boost of 0,6 bar, It may not come with the "pill" like the WRX which helps to increase boost pressure. I may nevet be able to set it up to do a 1.2 bar boost on my stock setup

Also just did a search in the NASIOC forum and another solution is to change a solenoid valve. Anyone has any experience with it?

You'll need to remove the turbo's heat shield. Then there's a 'c' clip holding the actuator to the arm. You'll need to remove it- it's light, springy, small, and hard to find if it gets away when you pop it off. So remove it slowly and don't let it fly away.

Tighten it one or two turns at a time, then go log the results before deciding to tighten it even more.

Sound a little difficult. Will try latter.

One thing for sure though is that 75% is probably not high enought on the stock setup to get 1.2bar. So I should try a higher value, say 80-85%