Major Boost Creep

[LANDSCRIBBLE]

Firstly, ive read some of the threads on here about boost creep but i thought i'd share whats going on with my setup, and if anyone has any ideas/thoughts.

I have a HyperGear ATR43G3 internally gated turbo fitted to my R33 GTS-t, currently with a 14psi actuator on it. It see's 20-22 psi everytime with the actuator being fed straight from the plenum (bypassing the HKS EVC-S).

I havent pressure tested the line, but im almost 100% the vac line isnt leaking (fairly heavy duty stuff and a yr old or so).

Has a 3in bellmouth dump pipe to decat, then 3 1/2 to tip.

The actuator does push the wastegate arm, tested this by pumping some compressed air through the actuator line. the actuator arm is very loose and free.

The car is running a ViPec V44, and is actually tuned on 20psi. (Previous 18psi actuator wouldnt go below 22psi unless i put almost no pre-load on the actuator arm, which then caused it to creack open early)

Ive read that running rich and advanced timing can have an effect on overboosting. Apparently my timing and fuel maps are about double of what they should be..

My problem is the wastegate leaks if it doesnt have enough pre-load on the arm. Which im not able to do otherwise it spikes to 25+psi.

I just want to get atleast 15-16psi without the wastegate opening early, and then use my EBC to sort the rest out.

Car is going in for another tune on thursday so maybe ill see how they go when they cut some fuel and timing out?

[greensa14]

So you are getting 20-22psi when running straight off the actuator? YOu sure it is a 1bar actuator? If you are running a 1 bar spring you should see 1bar ~1-2psi, depending on exhaust, intake set up etc.

[SargeRX8]

My ss2 with a 17psi actuator made 25psi. Got it swapped for a 10psi one which couldn't do 5psi. Got that swapped for another one which does 12psi. They are weird actuators.

[LANDSCRIBBLE]

Im told it is 1 bar. Sarge what boost are you running now? And does it hold steadily or drop off in the top end? Cheers.

[lilcrash]

My 7psi creeps to 18, 14psi creeps to 22, 21psi I have never revved past 26psi. That's on an atr43 ss1

[SargeRX8]

Im told it is 1 bar. Sarge what boost are you running now? And does it hold steadily or drop off in the top end? Cheers.

I run 13 to 14psi low boost(all actuator with some gain to keep the line flat). High boost is 18 to 19psi. I'll get you my dyno graph, low boost is perfect, high boost tapers of up top but this could potentially be changed with some settings or a boost controller capable of controlling boost at x rpm.

[GeorgesR34]

As far as what I know when they did my PU high flow

I had the stock actuator that run on 7psi that tappered off to about 14psi with boost controller

Their 14psi actuator that held about 15psi with no boost controller and tappered off to 17psi with boost controller

Also their 20psi actuator that held 19psi flate to red line with no boost controller (That was the best) .

The 20psi far as I know is what they use as default.

[black bnr32]

try porting your wastegate port, and smooth the path into it

[rondofj]

How come we only hear of people with actuator/boost problems on Hypergear turbos and not Garrets or others??

[hypergear]

How come we only hear of people with actuator/boost problems on Hypergear turbos and not Garrets or others??

Thats the first ever case on a G3 I've ever seen.

Those turbine housings runs a 32mm internal gate port with a 36mm wastegate disc. Thats what we port the internal gate to on the Garrett turbine housings to when we rebuild or high flow their turbos. (mainly xr6 3582).

That gate can not be ported any larger as thats all the diameter there is before breaking into the walls. That can not be the cause.

Check the wasetgate assembly to see if its operational by shooting pressure into it from the compressor. Of it is then check vacuum source. or see if the actuator it self is operating of so make sure the rod is not fouling on the bracket.

[LANDSCRIBBLE]

Yep tested the waste gate with the compressor and its pushing the rod back and forth. The rod is "just" clearing the bracket it goes through. Maybe an even softer spring might work (12psi), like sarge did?

[StealthX]

Three things...

1. Do you have an adjustable actuator rod? whats your pre-tension like?

2. Try disconnecting the actuator rod and go for a drive, go WOT at high revs, 3rd gear. see if you make any sort of boost. If you make any more than 5psi then you've got a wastegate problem. The car shouldn't make more than a few pounds of boost on a correct turbo / rear housing / engine size combo.

3. Which rear housing do you have?

FWIW I had a genuine garrett 2860rs, had boost creep problems with the .64 housing, and not with the .86 (turbo was too small for a 2.5l though...)

[LANDSCRIBBLE]

Yes the rod is adjustable, putting 4mm preload on and it goes up to 22psi. Now with 2mm its still going up to 22psi. Last week I also undid and tied the wastegate arm to the fully open position and it made 11psi in 3rd gear. Im not sure what size rear housing it has to be honest

Edited March 13, 2012 by LANDSCRIBBLE

[StealthX]

Yes the rod is adjustable, putting 4mm preload on and it goes up to 22psi. Now with 2mm its still going up to 22psi. Last week I also undid and tied the wastegate arm to the fully open position and it made 11psi in 3rd gear.

You've found the source of your problem... With the wastegate flap wide open it still makes 11psi. Your target is boost 14 on the actuator, + 11 from the boost creep = 25, that's not far off your 22psi that you see... That's where your extra boost is coming from! Rule out the actuator and/or boost control, I reckon your rear housing is too small.

[DVS JEZ]

How come we only hear of people with actuator/boost problems on Hypergear turbos and not Garrets or others??

Kando internal gates are doing similar things

[LANDSCRIBBLE]

I was also leaning towards that Would running an even softer actuator work? perhaps a 9/10psi spring and just run no ebc. Bandaid fix yes, but it'll have to do for now. I just really dont want to run any more than 20psi.

[hypergear]

They run pretty large .82 rear housing. That actuator has been tested already, I delt it has some thing to do with the actuator or the wastegate assembly as there would be couple of hundred people here with the same issue. Try a different boost source and see if that makes any differences as I found it strange as the sping load made no difference in your car.

[JonnoHR31]

Your target is boost 14 on the actuator, + 11 from the boost creep = 25, that's not far off your 22psi that you see... That's where your extra boost is coming from!

thats not how it works....

try running no pre load (actuator only just holds gate shut with no pressure) and make sure it can swing all the way open when pressurised. then make sure you have a dedicated line directly from a boost source to the actuator and see what you get.

[LANDSCRIBBLE]

thats not how it works....

try running no pre load (actuator only just holds gate shut with no pressure) and make sure it can swing all the way open when pressurised. then make sure you have a dedicated line directly from a boost source to the actuator and see what you get.

I will try that (also recommended by Stao), other 2 things i've done.

I've attached a picture here and was wondering what you guys think. Im thinking maybe it is leaking air from somewhere when its hitting boost. but theres so many places that are able to leak from. (BOV is blocked off)

Is the boost source where it is on the plenum a good spot? Or should i get a nipple tapped/welded right after the turbo somewhere?

Thanks everyone for the input!

[JonnoHR31]

where does the hose from the t/b go? i cant remember. the bigger hose to the right is for idle air. dont block that bov hose unless its leaking.

boost source is fine, wouldnt hurt to pressure test the hose to make sure it doesnt leak though. your boost gauge will be reading off the manifold too, so if your overboosting according to that then boost leaks before the manifold arent the cause.