PhatManBUD

So i have a wastegate and the spring is set to 1 bar. But i do not want to run 14-15 psi all the time and i want to run around 10-11 on the streets. Obviously i cannot change the spring everytime.

So will a boost controller work at keeping the boost levels at 10-11?

Would a manual one work? or do i have to get an electronic one?

jreynish

iTrader: (2)

no,
if you want to run 10-11 psi all day long and just want 1 bar when you want to race or somehting then yes a good electronic boost controller will help you raise boost, a boost controller cannot lower boost, Now here ist he deal you need to purchase or install a 10 psi spring and use that then use the boost controller to raise boost when you want more... but you cannot have the 1 bar spring in there and use a boost controller to lower it, boost controllers make boost come on faster and last longer, you cannot lower boost with a boost controller.

PhatManBUD

Really?

Can you explain to me how the WG works. I thought it dumps at whatever the spring is at so you dont over boost.

So say i put a 10 psi spring in and wanted to run more if i turned up the boost wouldnt it all just end up going out the wastegate anyways?

I thought if the spring was set to 1 bar its meant to never go over that so you dont spike and overboost. So i was thinking with a boost controller id just be at 11-12 psi and it woulndt dump out the wastegate unless it had to.

bcty

the spring in the wastegate is the minimum the car will boost to so if u ahve a 14psi spring thats all you can do min. like said before if u want to boost less get a 10psi spring or so. Boost controllers only raise boost or keep boost the same just help spool faster

PhatManBUD

Really, thats helpful THANKS GUYS.


oh i had another question...i have like 7 springs and i odnt know which one is for which psi. Is there any way i can test them?

Bukwild

do you get any affects of using a smaller spring and usings the boost controller to make the extra boost? You would think that the car would get to full boost faster with just the larger spring.

DCrosby

The sping is for when there's no vaccuum/boost in the cyclinder to open the wastegate, so the spring is there as a failsafe device, and as a baseline.
Once you controll vaccuum / boost going into or out of the cyclinder on the wastegate you now override what the spring is set to, the thing is you can't negate the sping to get less boost than what the spring gives you unless you have a boost leak...

So you can always go higher on boost with ANY boost controller, but never lower than the wastegate spring.... so use the spring as a baseline.

To give you an idea, the stock twins have a 7PSI spring, singles vary on manufacturer, and size of the wastegate, and you usually can get different springs for more $$

PhatManBUD

really, thats good to know. Thanks dcrosby. sooo what happens when you put a spring in thats too little psi. can i just up the boost and it will run 11-12 like i want? or maybe i should take a guess with the springs?

so there is no way to test them?

maxcooper

The color of the spring can often be used to figure out what pressure it will give. Who made your wastegate, and what color springs do you have?

-Max

jreynish

iTrader: (2)

you company's instruction manual will tell you what colour spring is best to use,
and if you want to run a minimum of 10 psi then with a boost controller you can ramp up the boost to about what you want really. A boost controlller simple allows the pressure on both sides of the diaphram to be controlled either allowing it to open as per normal, or to open l8er (surpassing the wastegate spring resistance.)
I have a 10 psi spring in my car right now and boost controller set to 15 and is working fine.
Who is the manufacturer of your wastegate?

PhatManBUD

Its the same HKS Replica oakridge7 has

PhatManBUD

theres like a yellow one, a little darker yellow one, silver, white, brown, dark brown, some i see are obviously thicker then others.

jreynish

iTrader: (2)

here this is the best I could find.

PhatManBUD

those look like them. BUT GEEZ! 1.1 bar and up. i dont plan on running that. at all

hmm...well i did also get a brown one thats soft, possibly too soft
and another yellow one ands a little harder.
so think i should go with that yellow one and get a boost controller and go up from there?

tkuwaha

iTrader: (18)

I don't think this is a correct statement unless I'm reading it wrong. Spring keeps the wastegate "closed". Boost pressure has to overcome the spring to open the wastegate so that's why the spring dictates the lowest boost you can run. Spring is not a failsafe device. No boost pressure fed to the wastegate(i.e. disconnected pressure line from intake manifold to wastegate) will result in a major overboost situation!! Boost controller bleeds off some of the boost pressure before it reaches the wastegate. Here's an example: if you want to run 10 psi with a 7 psi spring, then your boost controller has to bleed off enough air so the wastegate "sees" 7 psi when the intake manifold pressure is at 10 psi.

cripsR6

I have a question(sorry if its a hijack), my manifold has dual wastegates with 7psi springs in each; does that mean that 7lbs is my minimum, or 14? thanks in advance

hIGGI

iTrader: (7)

7 lbs

MARTIN

The boost controller doesnt bleed pressure. It closes the solenoid untill you have the desired boost, then opens it allowing the air to flow to the wastegate, therefore opening the valve and keeping it at that pressure... A proper way to do a setup is to size the wastegate with the turbo. Too big of a wastegate and you can experience pressure loss. too small of a WG and you can have boost creap.

poorboyracing

tkuwaha

iTrader: (18)

I agree that an electronic boost controller keeps the solenoid closed until desired boost is reached(or close to it), then starts to open(or cycles) to maintain desired boost level. There is a difference between the stock turbo control system and an aftermarket boost controller with an external wastegate. However, in both cases, the solenoid does bleed or divert the some of the pressure going to the wastegate signal line to control boost. Stock solenoid is a 2-way, one nipple is connected to the wastegate actuator, the other to the intake side of the turbo(bled to atomospheric pressure). Aftermarket boost controller solenoid is a 3-way, one is connected to the turbo outlet(or intake manifold), another to the wastegate, then the third is open to atomosphere(bleed). The solenoid is controlled by duty cycle, and that determines how much pressure is bled off(very similar to how fuel injectors determine the amount of fuel supply). If it's just a simple open/close operation as you say, it won't be able to maintain the same boost level at different rpm/load conditions.

MARTIN

Ok, the nipple on the compressor housing is for the wastegate, it has nothing to do with bleeding pressure or anything like that... The wastegate needs a line with no vacuum, therefore it needs a feed line anywhere before the TB.. The only thing that the wastegate bleeds out is exhaust gas. It either opens a flap to divert the exhaust gas from the turbine or opens a piston which lets exhaust flow past the turbo(external). But it does not release any boost at all... most solenoids for boost controllers (if not all) only have 2 ports, In and Out, there isnt any 3rd port that releases pressure.

tkuwaha

iTrader: (18)

No, no, no, the bleeding of pressure I'm talking about has nothing to do with the exhaust gas pressure. Look at page F-84 of the factory service manual and follow the lines on the diagram around the wastegate control solenoid. For an external wastegate, look at this diagram. http://www.proturbokits.com/images/t...on_Drawing.jpg
For an electronic boost controller, the "vent" nipple on top right of the diagram would be part of the solenoid, making it a 3-way valve. You seem to be mixing up the exhaust side of the wastegate(flapper or valve) and the diaphragm side of the wastegate(actuator).

nopiston_racer

iTrader: (2)

sorry if this is a hijack...but when it was said about the size of ur WG vs the Turbo...how exactly do u know what is a good size....im running the Garret t04b with a 38mm Tial wastegate....its not installed yet and i was just wondering if that WG is big enough....

on another note i was looking at getting turbo timer...now do i need this?...or is it just to help regulate the psi......i know a bit about turbo's and what not...but im doing the install myself and i dont want to $%^& up my new engine...thanks..parker

MARTIN

all a turbo timer does is leave your car idling after you have removed the key from the ignition. It usually senses the boost and predetermines idle time from that. It is not necessary.