IWG not giving me desired boost
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The wastegate that came with my turbo was rated at around 7 psi.
However, the wastegate will open nowhere near that. It was opening around 21 psi. No matter how much I adjusted it, I brought it down to a minimum of 13 psi.
This is the turbo I have,
http://cgi.ebay.com/ebaymotors/T25-T...d=253266173196
So, I was wondering, does angling the wastegate slightly cause the wastegate to open at a much higher PSI then what it is rated. Here is how my wastegate was originally mounted.

Then I switched to another wastegate and brought it down to lowest 11 psi but I only want to run around 8 psi. But this wastegate is too big and I can't move it anymore to angle it better.

Do you suggest I try to buy the same wastegate that originally came with the turbo because maybe I bent the old one? Or what should I do?
Also, does having a 3" exhaust make any difference?
However, the wastegate will open nowhere near that. It was opening around 21 psi. No matter how much I adjusted it, I brought it down to a minimum of 13 psi.
This is the turbo I have,
http://cgi.ebay.com/ebaymotors/T25-T...d=253266173196
So, I was wondering, does angling the wastegate slightly cause the wastegate to open at a much higher PSI then what it is rated. Here is how my wastegate was originally mounted.

Then I switched to another wastegate and brought it down to lowest 11 psi but I only want to run around 8 psi. But this wastegate is too big and I can't move it anymore to angle it better.

Do you suggest I try to buy the same wastegate that originally came with the turbo because maybe I bent the old one? Or what should I do?
Also, does having a 3" exhaust make any difference?
It looks like in both pictures the rod is crooked going into the canister. That part needs to be a's straight as possible for it to function. Also, if that is the begi sgdp it has been known to boost creep slightly
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Yeah, that should be straight as possible. Cocking it may be causing the spring to have more pressure on it, thus making it open at higher PSI. You can test it...take a regulator with a gauge and a barbed fitting on the exit end of the regulator. Obviously have an air compressor supplying air on the inlet side of the regulator. Connect a rubber hose from the exit side of the regulator to the actuator. Start at zero psi and increase the pressure of the regulator until the actuator rod moves and opens the wastegate. Now you will know roughly how many psi's it takes for your wastegate to open.
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Would having a 3" exhaust change anything though? I can't think of any physics behind it that will cause it to change but I remember reading somewhere that it does.
Thanks guys for the help. I will go find a way to make it straight.
Thanks guys for the help. I will go find a way to make it straight.
Last edited by x8mrxjohn8x; Aug 7, 2011 at 04:47 AM.
I'm, in the same boat because my wastegate actuator is supposedly set for 8-9psi but I'm seeing 12-13.5psi.
-That WG rod is crooked as ****.
-Yes, a bigger exhaust makes a huge difference.
This is typical boost creep, port your turbine housing. Make sure the flapper doesn't hit the downpipe as it opens. If none of that works, you're going to have to make the exhaust/turbine less efficient. The best solution is an external wastegate but thats expensive.
I have a thread on the front page of this subsection talking about my issues with boost creep. May wanna do a search as well.
-Yes, a bigger exhaust makes a huge difference.
This is typical boost creep, port your turbine housing. Make sure the flapper doesn't hit the downpipe as it opens. If none of that works, you're going to have to make the exhaust/turbine less efficient. The best solution is an external wastegate but thats expensive.
I have a thread on the front page of this subsection talking about my issues with boost creep. May wanna do a search as well.
Cracking. My wastegate is for 7 psi and with a hand pump it barely starts to crack open at 7 psi. With the car actually running there is pressure pushing the flapper door open.
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For example, your wastegate is rated at 7-8 PSI, and actually runs at 10+ PSI,
so maybe a 3-4 PSI will actually run at 7-8PSI. lol
It needs to be connected to a source BEFORE throttle body. That is most the biggest issue. Also, crooked wastegate could definitely have negative effects on performance. Borg Warner says a max of 2 degrees from straight is allowable, although that is another brand
just my $.02







