Boost Creep??

[user904]

I was doing a steady 80mph this morning on way to work and though i'd push it a little. :twisted:

As soon as I planted my foot the boost gauge went up to 0.9bar as it always does but then slowly worked its way up to just over 1.1bar by the time I was at 130mph.

Is this boost creep?? If it is what can I do to stop it?? Is it bad news??

Engine mods are hks superflow induction, apexi s/s exhaust and baileys dump valve.........

I think Boost creep is when the wastegate cannot flow the correct volume of air which prevents the turbocharger continuing to increase the boost..

Not sure how or why its happening on your car Benny.. You have stage 1 mods but no boost controller?

[user904]

I don't have a boost controller yet.

I didn't think I'd need one with stage one mods. I was gonna get one when I got the Gizzmo chip along with Walbro etc.

Decat on way......... 8)

What should I do??

Pass.. According to a few sites I found on google a boost controller always helps with holding boost at the desired level.. I.E No fall off, spiking or creeping

[user904]

More money then!!!

Have you ever hit fuel cut?

[user904]

Is that when you're booting it and the car dies for a second or so??

No, never had this. Last rolling road I did the boost line and fuel lines were absolutley perfect, dead straight and no cuts or spikes.

Fuel cut feels like shit.. The engine stutters for a second and then power returns..

Not good for the transmission or engine..

I had fuel cut for a while but swapped my actuator to an Evo VIII item and it fixed it..

Is the actuator looking a bit tired now Benny? Check to see what kind of condition its in

[user904]

Definatley never had a fuel cut.

Where is the actuator based?? Any pics to show me where I should be looking??

What does the actuator do then??

LOL.. NP mate..

Wastegate actuator

The primary function of a wastegate is to regulate exhaust flow through the turbo and control how much boost is generated.

A wastegate is simply a valve with a diaphragm and spring which is used to control the boost level. There are two forces acting upon the valve when you accelerate: exhaust pressure is pushing against the bottom of the valve, and the combined force of spring and air pressure is pushing on the top of the valve. The valve will stay closed until there is more exhaust pressure than resisting pressure. At this point, the exhaust flow starts to bypass the turbine, limiting how much boost is produced. The valve does not operate digitally. That is to say, the valve can be partially open, only bleeding off small amounts of exhaust flow. The balancing act between exhaust pressure and the combined forces of spring and air pressure is what regulates the amount of boost created.

Pic below of a wastegate actuator.. You cannot miss it.. Right next to the tubby..