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Old 08-12-2010, 11:15 PM   #1
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Default Internal wastegate actuators

I'm hoping that this will get moved to the useful saved posts after all of the responses are cleaned up.

Background:
My china turbo came with a 25psi wastegate. While my motor can easily handle this, I want run an EBC from about 14psi up to 22psi.


I recently bought a new WG actuator that costs almost 100 bucks after shipping. I would like to establish a list of quality internal WG actuators sorted by price. Obviously the ideal actuator would hold boost to it's rated psi, last forever, and cost nothing.

Your Input:

Please list from experience what you feel is the best external WG actuator for the money. We can separate this in to high boost and low boost applications since high boost applications will be more demanding on a wastegate and in my opinion require a higher quality piece.

Last edited by miatauser884; 08-13-2010 at 11:08 AM.
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Old 08-12-2010, 11:34 PM   #2
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The problem with internal wastegates (at least my problem) is that at high rpm's and high boost (over 20psi) the wastegates can't regulate the door properly. I can feel and hear the door fluctuating at wot. If you plan to run more than 19-20 psi go with EWG.
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Old 08-13-2010, 10:56 AM   #3
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Quote:
Originally Posted by levnubhin View Post
The problem with internal wastegates (at least my problem) is that at high rpm's and high boost (over 20psi) the wastegates can't regulate the door properly. I can feel and hear the door fluctuating at wot. If you plan to run more than 19-20 psi go with EWG.
This appears to be the common thing.

However, there are going ot be a lot of people that have completed their setup without thinking about an EWG. I'm included in this group. Rather than pull everything apart, weld the internal gate, modify my manifold, buy a new EWG, etc. I am just going to be happy with a less efficient setup. My DP will have a WG separator in place. Hopefully improving the operation slightly at high boost.

For those that are in my shoes; What are the best external actuators for the money.

I bought the 15psi Garrett WG from BEGI
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Old 08-13-2010, 11:02 AM   #4
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your title is misleading. external wastegate implies just that: an ewg. what you're actually talking about is an INTERNAL wastegate actuator. Just a heads up. I'd change title


but on the topic of wga's:
its a valve. I don't think theres much difference between the different brands, other than some are threaded/adjustable and some are not.
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Old 08-13-2010, 11:10 AM   #5
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Quote:
Originally Posted by 18psi View Post
your title is misleading. external wastegate implies just that: an ewg. what you're actually talking about is an INTERNAL wastegate actuator. Just a heads up. I'd change title


but on the topic of wga's:
its a valve. I don't think theres much difference between the different brands, other than some are threaded/adjustable and some are not.
SO, if psi ratings were equal. You'ed recommend a $35 chinese actuator over a $80 Garrett actuator? I juat want to make sure it is clear.
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Old 08-13-2010, 01:19 PM   #6
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I would think used Garrett actuators would be plentiful and cheap, since they don't really break.

How did you determine your actuator (chactuator?) is 25 PSI? That sounds ridiculously high. An EBC can control a WG which needs e.g. 6 PSI of spring pressure to hold 25+ PSI of boost, it just changes the control parameters.
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Old 08-13-2010, 01:22 PM   #7
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I reread the turbo documentation and kept boosting over 20psi into my boost cutoff point
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Old 08-13-2010, 01:51 PM   #8
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Quote:
Originally Posted by djp0623 View Post
SO, if psi ratings were equal. You'ed recommend a $35 chinese actuator over a $80 Garrett actuator? I juat want to make sure it is clear.
There really aren't many failures with wga's that I've seen. Or at least not many documented ones.

As said earlier, being internal the iwg is already limited, and that has nothing to do with the actuator itself.

So yeah, I wouldn't really see much difference between the two. one might be "better quality", but as we've seen with chinachargers, even a supposed "inferior" replica can get the job done, since its doing only 2 things: opening under pressure and closing without any.
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Old 08-13-2010, 09:55 PM   #9
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Quote:
Originally Posted by 18psi View Post
There really aren't many failures with wga's that I've seen. Or at least not many documented ones.
Some diaphragm-type actuators really aren't meant to see vacuum. If you connect your reference line to the intake manifold, the diaphragm will eventually fail and the wg will never open. You will split pistons and bend rods. To prevent this, always connect the actuator line upstream of the throttle plate.
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Old 08-13-2010, 10:04 PM   #10
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All wastegate actuators are not created equal. The stock one that comes with the greddy kit for example, sucks monkey *****. My boost needle was a blurr when I had it. I really wish I remembered which one I bought when I upgraded, but I honestly have no idea. It was somewhere around $50 shipped, and worked much better. It would smoothing and quickly move 2 or 3 psi above my target psi, and then slowly settle to 1 or 2 psi below by redline.

I just moved my wastegate source to right in front of the throttle body, and it now goes up to 9.5 psi and never budges an inch.
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Old 08-13-2010, 10:28 PM   #11
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I installed an HKS upgraded SR20 internal wastegate on my chinacharger. Cost $120, is set to 8psi, and has held a steady 13 psi.
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