[Mk2] [Turbo] Reaching 14PSI on actuator alone Rev 2

[toecutter]

Rev 2 turbo is reaching 14PSI boost just on the (standard) actuator.

TVSV is blanked off, boost controller switched off, should only be about 7PSI I thought? Didn't always do this, only since back together with rebuilt engine.

Only difference I can think of is the exhaust cam was retarded 6 degrees but don't know that would do it.

What could cause this?

[b4nk51e]

Cold weather

[Quigonjay]

decatted? other mods?

[toecutter]

Didn't think cold weather would affect it to that extent?



It is decatted, other mods that may be relevant are mongoose (I think) exhaust, CT20b, bigger side mount, enclosed induction kit.

Could the boost controller solenoid be faulty? Might be worth trying with it out?

[Peter Gidden]

CT20b

CT20 actuator I presume?

[jimGTS]

its creeps there due to the free flow setup
ie wastegate is too small.

restricting exhaust should bring boost down.
ie smaller exhaust, restrictor ring etc

or just learn to deal with it.

mine creeps, i just learn to run high boost



i assume it probably holds 7psi for a time, then slower creeps up top end

[toecutter]

I believe it is the CT20 actuator, turbo was on car when I bought it.

Next time I take it out I'll watch the boost to see if it is creeping up, I only took notice of what it was peaking at. I plan to run about 15PSI on boost controller anyway so if it is creep it's not too much of a problem.

[Peter Gidden]

I believe it is the CT20 actuator, turbo was on car when I bought it.

Well that's set higher than the CT26 actuator in any case. A CT20 decatted with freel flow exhaust will often hit 13psi as normal.

[toecutter]

Didn't know that, thanks

[jimGTS]

My ct20b actuator was 7psi.
So were the ones tested by Gaz.

Still see what you get.

[mrturbotom]

I have a ct20b on my rev2, hit 15psi on the actuator alone with an exhaust restriction. Ran a full 3" system and would hit 16psi on actuator, higher on cold days which would make it hit fuel cut even though I have a greddy fcd (apparently meant to remove cut but it doesn't)