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Maybe i do, ill try clarify.

Is there a difference between boost pressure and wastegate pressure? I always thought that wastegate pressure was a result of boost pressure?

What exactly is turbosmarts eboost2 claiming in this video?

Thanks for your patience.

they are saying it controls when the solenoid allows boost to get to the wastegate (solenoid closed = no pressure getting to the wastegate which should give reduced wastegate creep before full boost so boost builds as fast/hard as it can, if you lower it boost should build a little slower/smoother)

they are saying it controls when the solenoid allows boost to get to the wastegate (solenoid closed = no pressure getting to the wastegate which should give reduced wastegate creep before full boost so boost builds as fast/hard as it can, if you lower it boost should build a little slower/smoother)

right right, so a typical boost controller has no solenoid to stop pressure to the gate?

Boost controllers like the Blitz SBC are dual solenoid but they dont offer functions like gate pressure. The 2 solenoids are purely used to get a more accurate boost reading from 2 points, no?

Seems like this Eboost stuff is a step above the JDM stuff.

All boost controllers, whether manual or Electronic control gate pressure, by bleeding off pressure before it gets to the gate actuator, E-boost is no different.

+1 that seems to be what he's after

once a set boost pressure is reached, a diaphragm in the actuator moves to open the wastegate, boost controllers work by bleeding pressure away from the actuator so the wastegate stays closed, building more boost until the pre-set boost controller allows the actuator to open.

Not an exact, point perfect description but hope it makes sense to the OP.

Boost controllers like the Blitz SBC are dual solenoid but they dont offer functions like gate pressure. The 2 solenoids are purely used to get a more accurate boost reading from 2 points, no?

Seems like this Eboost stuff is a step above the JDM stuff.

Blitz use dual solenoids to quicken response and control (as it has double the resolution)

Blitz call the their version of turbosmarts gate pressure control "gain" so look for any controller that has gain functionality. Greddy call it "set boost"

What do you mean function? They both function in exactly the same way… and that is…

1. They ALL control the pressure via the wastegate.

2. They do this via the solenoid/stepper motor.

3. Dual solenoid just adds an additional element of control (I wont go into details about how “much” better single vs dual, plenty of threads on that)

So simply put - There is no way around this when using a EBC & external gate.

The eboost stuff is not specifically better than say… a HKS EVC6

You are getting confused with what they are calling “gain” as Trent has said. Its nothing more than one company marketing it as something else.

If it were me, I’d be using a EVC6 (which I will be doing shortly :bunny:)

Right right, if i may put out another question then.

Why do people run higher wastegate springs in their external gate when they can automatically control the pressure via boost controller? Why dosnt everyone run a 7psi spring compared to a 21psi spring?

When u say better boost control, what exactly do you mean? Having a higher boost spring would bring up issues like boost creep/spike wouldnt it?

Could people clarify how a cars response would be affected on the following setups

wastegate spring of 15psi, Peak boost of 20psi

wastegate spring of 10psi, peak boost of 20psi

both controlled via ebc.

Thanks for all your time guys.

Edited by Jap_Muscle
When u say better boost control, what exactly do you mean? Having a higher boost spring would bring up issues like boost creep/spike wouldnt it?

Could people clarify how a cars response would be affected on the following setups

wastegate spring of 15psi, Peak boost of 20psi

wastegate spring of 10psi, peak boost of 20psi

both controlled via ebc.

Thanks for all your time guys.

base wastegate spring of 10psi will generally taper down a few psi @ 20psi (say 3-4psi)

base wastegate spring of 15psi will generally taper down a few psi @ 20psi (say 1-2psi)

It is best to run a spring closer to your set pressure.

TTheory often doesnt always relate to real world results..... as manifold design turbo design, gate position etc all contribute.

but if you stick to one rule (It is best to run a spring closer to your set pressure.) you will generally be @ a good starting point.

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

10psi spring running 20psi is more likely to get gate creep

than

18psi spring running 20psi

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

www.hotstuffworks.com - Go have a search mate. Great site that explains the basic stuff.

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

EDIT: Trent beat me, damn using my mobile lol

You can control boost with just the wastegate e.g. RB20 with a single line to the actuator or an adjustable wastegate like the Synapse. The correct wastegate properly installed will not spike or creep. A boost controller (any one) is just delaying the action of the watsegate by bleeding off the pressure to the wastegate. Response can be varied a little bit by a boost controller which will delay the opening of the wastegate but ideally the wastegate will be doing most of the work and the boost controller is just a "trimmer".

[edit] better put by Trent

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