over boosting issue

[1JUM2NV]

Hey guys

Need some help here. I cant figure it out atm

Got my ute running again and it overboosting. Its not the boost controller tried a different solinod and its not the acturator as its brand new. It goes to what ive set it for but after 4000ish it creeps.

The ute is running a cop setup, full 3" zorst but factory dump, all the normal mods

Anyone got any idea on what it could be

 

[Missile]

Boost creep is pretty common, particularly with stock stock stock stock stock stock only modification a 3" exhaust. Simplified, by reducing the back pressure you are allowing the turbo to spool faster (overall rpm) as the air can now be (with exhaust upgrades) exhausted faster.

So you can either:
- Put some restrictions in your exhaust to gain some back pressure (e.g. non hi-flow cat etc.). But who wants to do that. Or;
- Help you wastegate regain correct function.

You may have a new wastegate actuator, but the wastegate flapper is where the issue will be coming from. The internal wastegate is the issue. So your best bet is to port the wastegate side of your dump, or look in to upgrading to the a new housing with the 34mm flapper.

 

[Benzo4gT]

Or go external and do this ↓↓↓

 

[Benzo4gT]

Seriously though, a flange with divorced wastegate about a foot long with low angle join up would be just awesome for internal

 

[1JUM2NV]

Future plans are to go external, but not for alittle while atm.

But if I got this would it sort of the issues..
http://www.4gtuner.com/topic/24013-25-stainless-dump-with-screamer-pipe/

 

[Missile]

Yeah and no.

Go to www.gtpumps.com.au and click "Housings"

 

[1JUM2NV]

If the dump will help as a short term thing I'll go with that, don't really wanna unbolt the turbo to change things. Dump is a lot easier to do

 

[Missile]

Really short answer in theory yes it may help.

What boost levels are you hitting?
And the boost is definitely holding until at your preset level for some time/range, and then increasing. Or is basically free boosting?

 

[1JUM2NV]

Yeah short.

Mostly driving on 15psi and yep holds til a rpm range then increases

Could it be cos it hasn't been driven for sometime too. Like I noticed on my way home it's holding better now for some reason

 

[Benzo4gT]

Yeah and no.

Go to www.gtpumps.com.au and click "Housings"

Get a Kinugawa housing, they're $200 as opposed to $341 and they are the same product right down to the stamping on the cast.

 

[EVOCPE]

Could be a stuffed wastegate. Mine did similar

 

[SKMsport]

A good test to make sure it is in fact the waste gate size being the issue,
Disconnect the actuator arm from the waste gate and tie the waste gate flap so it is fully open.

Take it for a drive, bring up the RPM's, it will be fairly sluggish as the waste gate is open fully.

But if it starts to over boost you know its the waste gate size restricting the air flow, and causing the boost to creep.

 

[4piknup]

Thats a good test.

 

[1JUM2NV]

It is indeed, will be trying that for sure

 

[trq-str]

http://www.4gtuner.com/topic/13632-how-i-solved-boost-creep/

 

[Benzo4gT]

http://www.4gtuner.com/topic/13632-how-i-solved-boost-creep/

↑↑ Now that is an awesome write up ↑↑

 

[1JUM2NV]

That is an awesome write up. I have a old td05 and my mates cheap Chinese 05 I'll look at aswell. Might check theses out and look at porting one of them