Wastegate question

Threshld1 · Post by **Threshld1** » Fri Feb 22, 2008 12:57 am

Hey was wondering if anyone had any ideas why im encountering the following issue. I have a v.2 90* inlet 16g ive been unable to run at anything less then 1 bar. I thought perhaps my EBC was acting up so i tried shorting compressor outlet to the wastegate and i still hit exactly 1 bar in top of 2nd on.
I was under the impression the wastegate spring on these were ~12.5 psi or so. Just in case its a 1 bar wastegate i threw on a TD04 actuator i know opens at 9psi. Same things happens, though it sits at ~10psi until 4.5k rpm and then makes it way to 1bar at redline.

Is the turbo just incapable of making less then 1 bar?

If it makes any difference im running stock manifold/up-pipe to an Invidia v.3 divorced downpipe

vrg3 · Post by **vrg3** » Fri Feb 22, 2008 2:08 am

Weird. Is it possible there's some strange restriction in the wastegate side of your downpipe?

Threshld1 · Post by **Threshld1** » Fri Feb 22, 2008 2:15 am

I checked clearance between the flapper and the divorced section of the DP. It has enough room to open as far as the actuator will allow. I had the compressor side ported but that shouldnt matter as the pressure is referenced off the compressor

vrg3 · Post by **vrg3** » Fri Feb 22, 2008 2:21 am

What about in the pipe?

Threshld1 · Post by **Threshld1** » Fri Feb 22, 2008 2:26 am

Not so much?
http://oksubaru.com/gallery/main.php?g2_itemId=3361

vrg3 · Post by **vrg3** » Fri Feb 22, 2008 5:20 am

Hm. I have no idea.

The stock TD05's wastegate actuator is supposed to regulate boost to about 9 psi, like the TD04 one you put on.

Just to clarify -- you're currently using the TD04 actuator and have it connected directly to the nipple on the compressor outlet?

Threshld1 · Post by **Threshld1** » Fri Feb 22, 2008 2:58 pm

That is correct. I also have the arm adjusted as loose as possible without it making horrible rattle noises at idle. Its really strange and bothersome since i have no control over boost. If i connect my EBC at even 0% set level (wastegate pressure) and a low gain or high gain it will jump up to 16.5 top of second.

vrg3 · Post by **vrg3** » Fri Feb 22, 2008 4:09 pm

I dunno, dude... That's so weird. Have you inspected the turbo carefully? Maybe there's something funny happening inside the turbine housing.

BAC5.2 · Post by **BAC5.2** » Mon Feb 25, 2008 2:03 pm

Use a pressure gauge and make sure it's actually opening at the levels you are seeing.

You don't have a leak in the hose you have connecting the outlet to the wastegate actuator, right? If you swapped actuators (with a known good unit) and the problem persisted, it's either a problem with the turbo or a problem with the hose. Check the hose. Then check the turbo. Make sure the wastegate arm CAN open fully with pressure (again, using a pressure gauge and pump. Make sure the wastegate is actually opening when air is applied to the wastegate. I know I had that problem on my old car at one point. I could move it by hand, but moving it by air it would snag up. I had the same symptoms as you did. A little grinding, and the problem went away.

Threshld1 · Post by **Threshld1** » Mon Feb 25, 2008 3:57 pm

Ill try it out with some air to the actuator. When you say you fixed a sticky actuator with some grinding, did you grind the rod where it was sticking or the hole by the diaphragm?

BAC5.2 · Post by **BAC5.2** » Mon Feb 25, 2008 5:39 pm

It was snagging in the downpipe. I simply ground out a little clearance and it worked fine.

93forestpearl · Post by **93forestpearl** » Mon Feb 25, 2008 5:40 pm

I think its time for an EWG

Threshld1 · Post by **Threshld1** » Mon Feb 25, 2008 6:35 pm

Haha thanks Dan, can you pull any strings over at Grimmspeed and get me one nice and cheap? I would LOVE to just weld that damn thing shut and go EWG but funds wont allow it and EM is more important.

Ill have to check the flapper again but without the actuator on it i can open it until it touches the side of the DP. Its much further then the actuator stroke is. I know there is atleast 1/4" clearance between the flapper and divider so i dont know where it would hang up. Thanks for the replies everyone!

93forestpearl · Post by **93forestpearl** » Mon Feb 25, 2008 7:24 pm

Have you tried replacing all the rubber lines for the BCS and actuator? A cheap way to rules those all out.

If you were able to get your hands on a wastegate, we could make it work. I have fobia's garage at my disposal, so we could add it to the up-pipe you already have. Then the question would be wether or not you'd want to recirc it. And yes, you do need some form of management very badly. You gonna get that G3?

Threshld1 · Post by **Threshld1** » Mon Feb 25, 2008 7:54 pm

Yeah ive replaced the rubber a few times now. Ill give it a quick check again though.

The EM with either be the G3 or an AEM EMS since i can get a good deal on them. I like the option of a nice PnP harness on the G3 but i also would like the auto base tune feature for my inexperience, well see.
It really depends on how much money the tax fairies give me, and then how much of that goes into the rally car. Damn expensive gravel coilovers...

If i find a deal on a Tial or something we can go at it but im not planning on it. It would definitely have to recirc after hearing yours, and im not too avid about getting midevil on my Invidia DP

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Wastegate question

Wastegate question