Boost Controllers That Control Gate Pressure?

[Jap_Muscle]

You get gate creep from having TOO WEAK of a base spring rate, not too high.

Gate creep = gate creeping open before desired boost level. Most commonly attributed to weak gate spring rate.

That seems to make sense. A weak speing will allow the gate to creep open before the peak boost pressure is reached. but shouldnt this problem be fixed with the boost pressure bleeding off that presure until the peak pressure is reached?

No wonder you have issues with your setup currently, sounds like your tuner/building is feeding you rubbish

EDIT: Trent beat me, damn using my mobile lol

lol, i blame myself. i definitely should read more

[R31Nismoid]

That seems to make sense. A weak speing will allow the gate to creep open before the peak boost pressure is reached. but shouldnt this problem be fixed with the boost pressure bleeding off that presure until the peak pressure is reached?

No because 10psi to 20psi sometimes can just be too much for the EBC to bleed/hold.

Hence you always run as close, to give the boost controller the best chance possible.

[wasnt me]

No because 10psi to 20psi sometimes can just be too much for the EBC to bleed/hold.

Hence you always run as close, to give the boost controller the best chance possible.

yep what nismoid said... when you start running a big difference between actuator pressure and actual boost pressure is when

you sort out the good from the bad boost controllers IMO.

my car for example has a 14 psi actuator. actual boost its holding 27psi!!!!

this is far from an ideal set up but will do till i can source a bigger actuator...

[JonnoHR31]

yep, always a good idea to pick a spring as close as possible to your target boost, to make sure theres no problems.

most of the time you'll get away with weak springs, for example i have a 7psi spring and have no problems running 25psi, but sometimes it just causes too many headaches

also, on most ebc's gain is different to set gain/gate pressure. for example on the profecs set sets the % of duty cycle then you use the gain to control how hard or slow it comes onto boost and holds in the top end then set gain or start boost sets the boost pressure the solenoid lets the gate/actuator see boost pressure at all. general rule of thumb is to set this 2-3psi below your target boost pressure

Edited November 25, 2010 by JonnoHR31

[D_Stirls]

You seem to forget that the wastegate has pressure on it from the exhaust gasses as well. It's not uncommon to see exhaust pressure twice what the intake pressure is so if you have a light spring you will be getting the pressure on the gate from the exhaust being too great for the actuator. Therefore even with no boost signal to the actuator you will still be seeing the gate opening.

Think about balance of forces.

EP= Exhaust Pressure

SP=Spring Pressure

BP=Boost pressure (on the diaphragm of the actuator)

For the gate to stay closed;

BP+EP<SP

So if the EP is greater than the SP even without BP the gate will open. Therefore a bigger SP is needed to stop creep.

External gates though are a different story as you can setup some EBC's to put pressure both sides of the diaphragm untill you want to open the gate and then they remove the pressure from one side of the diaphragm allowing the gate to open. In this case the pressure above the diaphragm helps the spring to hold the gate closed.

Really might be able to achieve the same thing with an internal gate using a duel port actuator but i haven't tried it personally.