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Hey all,

So have a GT3076 internal gate on my r34 GTT.

I made the switch from external to internal for a more stock look :/

SO boost creep...

I have a full 3 1/2 exhaust with no cat, bell mouth dump.

12 PSI actuator, and reaches that then climbs to around 16- 17.

With my current set up the level of boost im ok with, but my question is is 16-17 the limit of creep?

Or if i raise the boost level to say 14, will it then proceed to creep 18-19?

My end result is wanting to reach and hold 16.

Im hoping to not have to port the gate, but im thinking that i will have to.

Thanks in advance.

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hey guys at the moment i am relying on the actuator. there is no point trying to control the peak of boost creep with a controller.

The gate is the issue, its not bypassing the gas quick enough.

But what i want to know is will the creep increase if i increase the boost with a controller?

hey guys at the moment i am relying on the actuator. there is no point trying to control the peak of boost creep with a controller.

The gate is the issue, its not bypassing the gas quick enough.

But what i want to know is will the creep increase if i increase the boost with a controller?

No it shouldn't.

The volume of gas shouldn't change so it should just spike to the same level

Some 3076's have perfect boost control.

But this is the 2nd one ive heard that creeps in 2weeks. Havent seen it with my own eyes tho.

What actuator are u running?

Have u tried applying regulated compressed air to the actuator to ensure the wastegate flap is opening 100% in its throw?

Its possible the actuator is incorrect

when i was considering internal wastegate, im pretty sure MTQ said there was two different types of housing, one was suited to lower power and had a different size flapper, somthing to that effect..

dont know if thats your issue but could be.. i also recall Mafia mentioning about the different housings and the wastegates being different.

Edited by SliverS2

Its a garrett 12 psi actuator.

I checked it with compressed air, and it starts to crack around 10psi, but didn't open very far.

how far are they supposed to open?

And Yeh its a .63.

Any ideas if porting the gate will help?

If so is there anywhere i can get a bigger flapper from?

Its a garrett 12 psi actuator.

I checked it with compressed air, and it starts to crack around 10psi, but didn't open very far.

how far are they supposed to open?

And Yeh its a .63.

Any ideas if porting the gate will help?

If so is there anywhere i can get a bigger flapper from?

They are supposed to keep opening as you pump more pressure in. You should almost get 90 degrees on the flapper

Normally the higher the engine revs the greater the amount of boost creep. I see that often. The only way out of it is to mill out the wastegate port and replace the original gate with one with larger OD.

IMAG1034.jpg

Thats my rear housing ^^^^^^^^

ok guys i have a gt3076 genuine garrett using a ford xr6 5 bolt style in a .82 and it had major boost creep i kno if you purchase it from garrett or gcg you can request a bigger flapper as i didnt know this till i got my turbo :)

this is a must do but make sure you measure the flapper and contact stao

will be fitting it this week hopefully it fixes my problem :)

Also ditch the garrett actuator and use the kingugawa internal wastegate mine was holding 15psi dead flat on my old gt3071 :)

Edited by jet2nv

Nice to know the Kando actuators work well. Is yours the CNC item jet2nv? I have one of those at home waiting to go on a mates car.

I also noticed it had provision for 2 ports.. I dont actually know how to hook that up yet but i might look into it for my own car.

  • 3 weeks later...

ok so a update fitted the turbo after having the larger flapper fitted and machined still OVERBOOSTS :(

im using a 1 bar actuator also used one of hypergears still hits the same boost 23psi

my next thoughts are maybe its the split dump pipe

any thoughts?

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