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That diagram looks the wrong way unless i am retarted ???

i vote yes for retarded :)

ok first, some simple theory on how it works. the screw presses down on a spring which pushes on a ball. the ball therefore stops some of the air pressure from the turbo (ic piping) getting to the wastegate, which then delays its opening (to limit boost).

therefore, the tighter the screw is, the more boost u get caquse the wastegate doesnt see its "7psi" until actural pressure is higher.

thereofre, the diagram is right - as u can see the screw acting ont he ball to stop air coming from the IC and going to wastegate

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Hi

Ok i have read the last 37 pages over the last couple of days before i start asking questions.

Im not understanding 100% how this unit can increase boost AND HOLD IT AT THAT LEVEL.

Correct me if i am wrong, but it works like this.

1. Boost will push up on the ball and spring until it overcomes the tension and pushes its way through to the wastegate actuator.

2. By then the boost would of built up past the "Stock" boost setting (which is determined by the wastegate spring)

Now the wastegate doesnt see anything until the turbotech opens up. Then all of a sudden it sees (for eg.) 12psi, which is more than enough to open the wastegate as it only has, say a 7psi spring in it.

NOW, the wastegate is fully open, wouldnt it keep bypassing exhaust gasses away from the exhaust turbine to bring it back down to 7psi?

So really it should hit 12psi but then drop back down to 7psi?????????????????????

Well just to update my situation everything appears sorted WOOT

Swapped the connectors over to the correct way lol and went out for a quick drive... let her warm up then put the foot down

went up to about 13/14psi so I backed off straight away.

Pulled over and wound it almost all the way out... back on the road put the foot down and went up to 9psi and held WOOT that’s a good start...

Pulled over again and wound it in a little bit maybe 3/4 of a turn if that back out on the road foot down hit 12 psi for .02 of a second then dropped and held at 11psi all the way up to about 5700rpm when I backed off as the speed was getting a little high.

so big cheers to all for the input ps this boost controller rocks so much better than my turbosmart boost T which couldn’t hold its boost and cost 3 times as much :)

Now the wastegate doesnt see anything until the turbotech opens up. Then all of a sudden it sees (for eg.) 12psi, which is more than enough to open the wastegate as it only has, say a 7psi spring in it.

its a ball and a spring, not a switch.

12 psi going this way -> | <- say 5psi of ball/spring pressure pushing this way

= net effect of 7psi that way ->

that is, once the ball spring is pushed away, you are still "using up" some of your pressure to keep it open - thus the wastegate wont suddenly see 12psi, it will be just as if its see "x psi" less than the pressure you have. eg it might be seeing 3 psi less pressure than is really there, so it opens at 10 vs 7.

its a ball and a spring, not a switch.

12 psi going this way -> | <- say 5psi of ball/spring pressure pushing this way

= net effect of 7psi that way ->

that is, once the ball spring is pushed away, you are still "using up" some of your pressure to keep it open - thus the wastegate wont suddenly see 12psi, it will be just as if its see "x psi" less than the pressure you have. eg it might be seeing 3 psi less pressure than is really there, so it opens at 10 vs 7.

O ok then.

well how would it bring on boost quicker? Im assuming that the ball and spring will "Creep" just like the spring in the wastegate would - causing wastegate creep.

sorry bout the questions but im really after something that can retain my standard boost (or as close as possible) but bring boost on quicker.

I 2nd NewKleer... that is my understanding of how it works, and it is able to hold a stable boost level much better than a bleed-setup.

And CEF11E, I think EVERYONE owes you a beer! =-D

well how would it bring on boost quicker? Im assuming that the ball and spring will "Creep" just like the spring in the wastegate would - causing wastegate creep.

wastegates arent an exact on/off - they start to slowly open before their specified psi rating.

bleed valve works like as if there is a little hole in the pipe from turbo to wastegate. it is subtracting a percentage of the air going from the turbo to wastegate, in order to lower the number that wastegate sees (the amount bled off does change depending on how much psi you have)

a ball/spring creates an initial restriction. instead of subtracting a percentage of air, its providing an absolute restriction (that doesnt change depending on how much psi u have)

mathematically, it would be somewhat like:

bleed valve:

real psi * bleed factor = wastegate psi (where factor < 1, eg 0.5)

ball/spring:

real psi - spring psi = wastegate psi (where we model spring as providing a resistance in terms of a specific psi)

so say you have 7psi wastegate, you want 14 psi

bleed valve:

14psi * 0.5 = 7psi (hence our factor for the bleed valve is 0.5, ie only half the air is getting to wastegate, other half is bled off)

ball/spring:

14psi - 7psi = 7psi (hence our spring psi is 7).

now, the reason its said to build faster can be seen when you apply those factors to when we are say, 3/4 way there (to 14psi). so lets say real psi is now 10:

bleed valve:

10psi * 0.5 = 5psi seen at wastegate - it may start opening, hence slowing buildup to max

ball/spring:

10psi - 7psi = 3psi seen at wastegate - wont start opening yet.

so you can see, the wastegate will start to open (hence boost build up is slower) with a bleed valve as you approach the target psi. i should make it clear however, the ball/spring isnt a perfect "absolute" value, its more likely to be somewhere between whats been shown here and the bleed valve - but still for demonstration purposes, you can see why the ball/spring is theoretically superior.

hope that helps

Edited by NewKleer

Thanks dude it makes it now bit clearer.

Ok now how close can i get it to stock boost by using this device? im really after the boost comming on harder and earlier rather than running more boost?

anyone here running their controller in this fashion?

cheers

Ok now how close can i get it to stock boost by using this device? im really after the boost comming on harder and earlier rather than running more boost?

I guess you have a couple of factors to take into account even with the stock solenoid hooked up after i put a full exhaust on boost was already up at like 8psi which was still running the stock setup...

As I said before i bought one and wound it pretty much as far out as i could and it was holding 9psi which i was impressed with.

hey guys just wondering ive been reading this thread for months and havent actually found any for sale on ebay or on the forums, whats the contact details for the bloke is he still making them?

saw some red ones on ebay but was worried about dodgieness if it wasnt the same materials, they were more expensive too

hey guys just wondering ive been reading this thread for months and havent actually found any for sale on ebay or on the forums, whats the contact details for the bloke is he still making them?

saw some red ones on ebay but was worried about dodgieness if it wasnt the same materials, they were more expensive too

Ebay link to Turbotech

Hey guys,

Recently I opened up my controller and the ball and spring fell out. I'm just wondering which way does the spring go? One side comes to a flat finish while the other side of the spring is open (if you get what I mean).

Edited by Scandrew

I'm having issues with trying to set my boost. I'm trying to set it to 10psi but it either only hits 8-9 psi, so I slightly adjust it for more boost then it starts hitting 14-15psi. Can't seem to get it in between? Could the diamater of the vacuum hose connecting to the boost controller be causing this?

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