Actuator Waste Gate And Solenoid Valve For Dummies

["Captain Retard"]

Ok I've done a fair bit of reading but still haven't found what I'm looking for which is;

How the actuator for the waste gate works in relation with the solenoid valve on these cars?

I'm pretty mechanically minded and understand the principles of turbo charging but as this is my first turbo car , I thought I'd ask what maybe a dumb question to most of you guys on here.

I feel I do have a boost issue but until I understand the above I'll save it for my next dumb question!

My car is a BA Typhoon 05 and apparently stock. I say that because it was heavily moded in the past.(not by me)

Answers, sarcasm etc would be greatly appreciated .

Thanks!

[Wilko16]

Google "closed loop boost"

First result will explain it, second is a video

Will explain the action of the solinoid...

Basically as far as I can tell it lets it boost slightly faster and more control

[Wilko16]

Also what's your "dumb question" ?

As long as it's not about a police edit, or chip most people will help you on here

["Captain Retard"]

Thanks Wilko, will google when I get home, just finishing up at work.

Still working on the draft for my next dumb question........ But it's coming!

["Captain Retard"]

Googles great when you type in the right info, THANKS WILKO!

So let me see if I've understood "closed loop boost" correctly.

What I see at WOT on the boost gauge is the boost get to maximum fast because the solenoid valve is limiting the amount of pressure the waste gate actuator sees.

The turbo builds pressure quickly(spools up quicker with less lag) and when the ECU sees a certain pressure it lets the waste gate start to take over by letting it see a truer pressure via the solenoid valve.

And as revs start to rise higher the boost starts to taper off a bit as the waste gate opens more and more.

Is that about right or am I still missing something.

I still have some questions but I'm old school and like to try and understand how things work first so I can understand the answers.

Thanks again Wilko, great vid, I love graphs, so much info in only a couple of squiggly lines!

[FiftyOne]

Just to confuse the matter, there are also interrupter solenoids which can adapt to rising boost quite a bit faster than the setups found in our cars. I haven't come across anyone that has swapped one out but I have a lot of questions for anyone that has

[Wilko16]

No worries mate, yeah I think you got idea

I was the same as you, was baffled until I got the right info,

Fifty one - I have also read about 4 port solinoids, and waste gates that have two ports, so they use pressure to hold them shut as well...

There is so many things some engine ecu's can control from calculations

[FiftyOne]

Keep in mind it's not just calculations, it's also predetermined maps from everything. For many of these tables there are also compansation tables as well. the boost control, as well as the fuel has a KAM that learns & adapts to how the engine is.

Ford spent a lot of time & money making the NHV on thiese cars as good as they are, making them perform, while also being comfortable & drivable. For people that think you can just wind up the boost with all your bolt on bits, think again. Main reason I'm interesting in the 4 port/interupters is because with a lot of tuning you can potentially control whats happening right down to a tee which could aid in the drivability of the car esp after fitting a larger actuator spring

[Wenier]

The basics of it are that the spring in the actuator is aided by the air that's feed to it. So the spring should hopefully be strong enough to hold to a certain level then add the air to open it up and control the boost.

[CHLAXN]

If I remember whrn I sold it it still had a bigger flapper on the exhaust housing with stock actuator. Also the intank fuel pump was a walbro 340 which were the only 2 things that were not returned to stock when I sold it. No idea if they are still on it 4 years later