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-   -   Adjustable WG actuators for stock turbo (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/adjustable-wg-actuators-stock-turbo-860755/)

Unseen24-7 09-01-09 11:49 AM

Adjustable WG actuators for stock turbo
 
Hi,

I was just wondering if anyone makes replacement actuators with higher spring tension and are adjustable?

Thanks

j9fd3s 09-01-09 12:30 PM

Hks

Unseen24-7 09-01-09 01:03 PM


Originally Posted by j9fd3s (Post 9466626)
Hks

That won't be cheap. There must be others.

arghx 09-01-09 01:16 PM

It's HK$. I'm sure they just rebadge the Garrett ones and mark it up.

http://www.atpturbo.com/Merchant2/gr...GT-033_450.jpg

Here's one that appears to be for hybrid turbos: http://www.atpturbo.com/Merchant2/me...egory_Code=BCS

ATP sells other ones. There are different types of brackets and other configurations for them. Some are dual-port style, like this one from turbonetics:

http://www.verociousmotorsports.com/...a036f5faf5d3f4

http://www.verociousmotorsports.com/...tuator-7-5-psi

the dual port actuators are hooked up like external wastegates. The pressure applied to the top chamber helps keep the wastegate swing valve closed for finer control.

Unseen24-7 09-01-09 02:40 PM


the dual port actuators are hooked up like external wastegates. The pressure applied to the top chamber helps keep the wastegate swing valve closed for finer control.
That is only for EBCs right? Or is there a way you can hook up a MBC to use a dual port actutator?

arghx 09-01-09 04:33 PM

you would have to hook it to the bottom chamber and run it like a single port actuator.

Let me ask you something: is there a reason why you want a stiffer actuator on a stock, non hybrid turbo? the boost is still going to fall off if you increase the tension in the actuator.

Unseen24-7 09-01-09 10:14 PM


Let me ask you something: is there a reason why you want a stiffer actuator on a stock, non hybrid turbo? the boost is still going to fall off if you increase the tension in the actuator.
For curiosity sake mostly, but I recently ported my wastegate and now the boost response kinda sucks, which from what I've read, is cause by the exhaust pushing past the wg flap before its open. I was just wondering if there was an option other than adding a spring to the actuator. And also I might decide to hybridize my turbo in the future.

I think I'm going to modify the actuator rod to be adjustable so I can increase the tension.

Which brings up another question I've had...

If I shorten the actuator rod, will that accomplish the same thing as adding extra springs to the actuator? If not, how do you add springs to the actuator as it is a sealed unit and I don't want to wreck the diaphram or anything.

arghx 09-01-09 11:37 PM

Shortening the rod increases the tension. It's like using a stiffer spring in an external wastegate--it increases the minimum amount of pressure the turbo will run, assuming it can flow to that pressure. As far as adding extra springs, I've never heard of someone doing that on an internal wastegate. I always thought the chamber was sealed and unserviceable on most/all internal wastegates. Also, are you sure you didn't over-port the wastegate so that the flapper isn't sealing fully?

A dual port actuator will allow you to push the wastegate closed so the exhaust won't open the swing valve unintentionally. It also gives you finer control over the rate at which the swing valve opens, provided that you have a precise enough boost controller (like an AVC-R or something built into a standalone that lets you set solenoid duty).

I'm not sure if it's worth the $80-$100 it's going to cost you for this experiment, not unless you plan to build your own hybrid at the same time or otherwise upgrade the turbo somehow.

Unseen24-7 09-02-09 08:03 AM

Thats what I wanted to know. I went fairly big with my wg port, (about 30mm iirc) and I welded on a bigger washer. It was a pretty good seal I thought, but if shortening the actuator rod doesn't work, then I guess I'll see if I can make the flapper seal a little better. I tried to make sure the new flap overlapped te port by about 2mm all around.

Another thing I noticed was since port my wg, I can't even hit 5psi. I get about 3psi in 1st and about 4psi in all the rest of the gears, even in 5th. I know the low boost has to do with the wg because I pulled the wg signal line off one day and boost shot up to 7+psi (I let off the throttle when it hit 7 cause I wasn't sure how high it would go, probly at least 10).

arghx 09-02-09 09:03 AM

if boost shot up to 7+ psi with the wastegate disconnected, how do you know that exhaust is pushing the wastegate open?

Unseen24-7 09-02-09 09:58 AM

Ok, Sorry, I should've worded that differently. It still was a little laggy (not as much as when the wg was connected), but boost went up to 7+. It didn't "shoot up", as in respond very fast.

I guess I'm a little confused then. Because if the wg is working(sealing) properly, shouldn't my boost be 5.5psi as that is what the spring is? Before I ported the wg I boosted 6psi regularly with very minor creep to about 7psi max in 5th (probably due to my restrictive exhaust).


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