You should just get a TRUE 1.5bar actuator. Bolt it on, plumb it direct to the turbo, and then run no boost control.

Problem solved.

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Doing it for all the wagons out there

^ try that Brett. U will know instantly.

I have a one bar actuator from my GT 2871 u can have.

using the Perth-WRX mobile app

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MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport

I have the following factory springs and hence I am now running the stiffest in order to test that the gate was not opening under back pressure.

0.8 bar = 11.6 psi
1.2 bar = 17.4 psi
1.65 bar = 23.9 psi

Um, you might have missed the point buddy.

Virtually all turbo's will boost high & hard with the boost line disconnected from the actuator. (E.G My actuator line split & it hit the 1.75 bar ECU overboost cut)

There simply isn't enough exhaust gas pressure internally to force the wg open against the spring pressure alone...... The actuator requires the pressure line from the comp housing to work as designed!

Remember my base wg pressure is only 13psi, that split hose saw a boost peak of 25.5psi on my set up - see my point?

(In fact I can run anywhere from 13 - 30psi on my set up, my WG duty for 28psi is only 45%)

You need to determine your gate pressure by bypassing the solenoid - but running a line from the comp housing directly to the wg actuator is the only way - there is no otherway to do this safely or accurately.

This will tell you your TRUE base line 'waste gate pressure' and will tell you a butt load about your set up.

I'm not flogging a dead horse here, but you need to properly determine you base line boost pressure before trying to find other faults that may not exist.

Grimspeed use rebranded MAC valves - I've only ever seen one fail (leaky valve seat) and that caused random boost spikes.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Go back to basics.......

Install the 11.5psi spring and leave the solenoid out of the boost control loop (run the line direct from comp housing to actuator).

Run the car up at WOT in stages - monitor boost - You should see a flat 11.5psi from spool up to redline.

If over or under 11.5psi adjust wg preload as previously stated.

Once this is know to be set up correctly then add the solenoid back in & adjust wg duty to reach targets as set.

Doing anything else is just going round in circles.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Well clearly. The 'rated' pressure of these spring/actuator does not match up with the actual pressure. If it did, then it would be impossible to get lower boost than the wastegate pressure. Unless you had some very serious mechanical issues. (didnt leave a rag in the intercooler or something like that when you had it all apart?)

Do as me and Rosco have suggested a number of times now, and do a run with the wastegate hooked directly to the turbo, bypassing the EBCS. If you only get 12psi with this so called 24 psi spring. Then the actuator is a piece of shit. Do as i said and remove the actuator and get on that actually works as intended and try that.
.

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Doing it for all the wagons out there

He could use a Mity Vac or similar tool and manually pump up the actuator and observe what pressure it extends at. It wont give an 'exact' wastegate pressure, but it will be accurate to within a couple of psi.

This is probably a very good test at this stage. He needs to know if the actuator is infact working.

Could also hook a boost guage up to the wastegate pressure hose and observe the wastegate pressure that way. Perhaps the wastegate is infact seeing 24psi when it opens but there is a blockage (like a rag in the intercooler) and causing a restriction and pressure drop so that the pressure observed in the manifold is only 12 or whatever?

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Doing it for all the wagons out there

Bram - I wouldn't do a closed loop test with that 24psi spring in there - too much risk of over boosting.

Safe gate pressure is 11-13psi - so it should be set up with the lowest rated actuator spring.

If he cannot achieve a flat 11-13psi using the available adjustment of the actuator rod then there's something else going on as you said.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Well hes already got the 24 in there and cant even get anywhere near it. So it wont matter whether he hooks it up with or without the EBCS connected. Remember the EBCS can only control boost ABOVE the wastegate base pressure, below wastegate pressure it doesnt matter how much pressure you do or dont bleed away, it wont really make a squat of difference. So straight away we know there is nothing wrong with the EBCS.

But yeah, still probs a good idea to test the lower springs first.

The only 2 options are as ive said, a faulty wastegate actuator that isnt opening at its advertised pressure. Or something weird like a massive blockage or leak in the intake or exhaust.

Need to properly test the actuator off the car. That way you are getting an acurate test of the actuator alone, without the variable of the car.

I have a mity vac.

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Doing it for all the wagons out there

Hopefully I am hearing what you are saying but we know that the springs are rated to a certain pressure as they are made by the actuator manufacturer.

With the early testing the solenoid was not lifting boost above spring pressure and so we thought that we had a solenoid fault as the gate should have stayed closed if it was seeing boost pressures of less than spring rate. Disconnecting the boost line to the actuator showed that the gate was staying closed and that the turbo was able to easily go beyond spring rated pressure. In that case we went to 15psi against a spring rate of 12 psi.

I swapped out the solenoid to test with a different solenoid. Both reacted the same. I either have two broken solenoids or two that are working.

I then went and swapped wastegate springs to see what impact that will have. I am only in the early stages of testing this and will have limited time for the next two weeks.

It is good to hear both of your input and ideas. I will consider it all again more fully when I have some time free tonight.