Ebay Turbo WGA Question

[skyrone]

ok for anybody who wants to jump down my throat i did in fact search for a good amount of time and i could not get the wording right on this. I need to figure out a way to get my waste gate actuator to travel more. It is already adjustable but i need it to go farther and still be able to fully close. I don;t neccesarily need an answer if u wanna just bombard me with links and tell me how dumb i am. thanks

 

[kenamond]

Mr Peepers is the expert on this, but as I recall, you cannot change the throw distance on the WGA. All you can do is adjust the preload on the internal spring in the WGA. The "Peepers mod" to the e3b16g WGA is to hack two apart and weld them back together to increase throw. Maybe you could PM him. Are you creeping?

 

[JusMX141]

You can do it by using the angled baseplate of a Mitsu actuator and welding a T25 actuator onto the baseplate, then joining the rods together.

I have one like this at my shop....I'll post pics later.

T25 actuators have twice the throw of a Mitsu actuator, and doing this mod is a hell of a lot simpler than what Mr. Peepers did (not to discredit him one bit!)

 

[skyrone]

i am in fact creeping. i just pulled it apart last weekend and ported it all out and it does ALOT better but still creeps slightly i would like to completely eliminate this so if i could figure it out thatd be sweet. I was thinking about shortening the arm thats 90 degree arm thats connected to the actual flapper because that would give me more rotation for the distance traveled by the wga arm if you understand what im saying. but i think ive read that its a pain in the anus to get all of that to line up so that you dont get things jammin up

 

[skyrone]

You can do it by using the angled baseplate of a Mitsu actuator and welding a T25 actuator onto the baseplate, then joining the rods together.

I have one like this at my shop....I'll post pics later.

T25 actuators have twice the throw of a Mitsu actuator, and doing this mod is a hell of a lot simpler than what Mr. Peepers did (not to discredit him one bit!)

I would like to avoid hackin anything up but i will do what it takes to keep from creepin. so r u sayin to put the t25 wga on the 16g? ### im sure i could do that pretty easy. ive gota t25 on hand.

 

[JusMX141]

I would like to avoid hackin anything up but i will do what it takes to keep from creepin. so r u sayin to put the t25 wga on the 16g? ### im sure i could do that pretty easy. ive gota t25 on hand.

Right. I'll be around my shop sometime tomorrow....I'll take some pics and get them posted up.

I know you don't want to "hack", but all Mitsu actuators have limited throw so no matter what you do you'll be in the same situation.

 

[Icarus]

Just had a crazy idea about this problem. What if the arm were shortened. All it would take is a ruler to determine the how much should be removed. First by measuring the current throw of the actuator. Next find the travel of the flapper in the ported housing. Then find the point on the arm, when closed, that meets the actuator's throw and the flappers arm position at full open. I tried to draw a diagram, but I am at work and my resources are limited.

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The red, modified throw, line is the same length as the blue, original throw, line. In theory you should be able to open the flapper completely the without changing the actuator.

 

[JusMX141]

Wow, a shorter center-to-center point of the arm...genious! It would effect the leverage needed to open or close the flapper, but it would be worth trying for sure.

 

[kenamond]

Two things to talk about here...T25 WGA and shortening the WG lever:

Shortening the lever is a good idea at first glance, and (not to discredit your ingenuity) has been suggested before. But here's the rub...

If you shorten the arm, you decrease the mechanical advantage of the WGA on the actual flapper. The turbine housing upwind of the turbine has a high back pressure when boosting (roughly twice your boost level on the cold side), and the flapper has to resist that backpressure. That's why all of the WGAs are preloaded. They hold the door shut against that backpressure until the WG is told to open. If you decrease the lever length, you increase throw but decrease torque on that flapper shaft that connects the lever and flapper. Folks who have upgraded to the larger flapper on the 16gs have had problems with the flapper sealing while building boost, because you've increased the area of the flapper that the backpressure is acting on, and the preload in the WGA isn't enough to resist that extra force. It *might* works, but it's certainly something to consider before you start.

This ties into the T25 WGA as well. The T25 actuator has a weaker spring. It has less preload. Therefore, it may not hold the WG flapper closed while boost is building. Again, this *might* work, too, but it's yet another thing to keep in mind before you start.

The Peepers mod takes a 16g WGA and increases the throw without decreasing the lever arm length or the preload. If you could just buy one like this, that'd be a big seller for e3b16g owners, I'd bet. But for now, we're left to our own devices.

If the T25 throw is a lot longer than the 16g, it might be that you could *increase* the lever length a bit to get *more* mechanical advantage (to compensate for the lower preload of the T25 WGA), but still have enough extra throw to open the flapper enough to dodge creep. I don't know. If someone had both WGAs, a spring scale, and some basic physics skills, they could probably test this out and see if it would work.

 

[Icarus]

I was thinking that the amount of force required for the correct operation of the system would not be compromised by shortening the lever by 3/16".

I figured it had been tried before but don't remember ever coming across it. Just seemed like a cheap and simple mod. But, like most things DSM it's probably been tried and if it's a sound idea that requires little money and modification, everyone would be doing it. On the off chance that it hadn't, I thought I'd throw out the idea.

 

[kenamond]

I was thinking that the amount of force required for the correct operation of the system would not be compromised by shortening the lever by 3/16".

I figured it had been tried before but don't remember ever coming across it. Just seemed like a cheap and simple mod. But, like most things DSM it's probably been tried and if it's a sound idea that requires little money and modification, everyone would be doing it. On the off chance that it hadn't, I thought I'd throw out the idea.

Unless I screwed up the trigonometry, you'd need to shorten the lever to be 36% of its original length to change the angle from 30° to 90° with the same throw. That will also decrease the force on the flapper to 36% of what was being applied before by the preload in the WGA. Obviously, you could run the numbers for something other than 90°, but that gives you an idea.

The equation I derived to get that percentage number (call it "P") would be P=100*sin(ANG1/2)/sin(ANG2/2) where ANG1 is the original throw angle (I used 30°) and ANG2 is the desired throw angle (I used 90°). So if the lever length to get a rotation of ANG1 is called L1 and the lever length to get a rotation of ANG2 is called L2, then L2 will be P percent of L1. Also, the force applied to the flapper by the WGA preload will be P percent at L2 of what it was at L1.

To go from 30° flapper rotation to 45° rotation means the new lever has to be 67% of the length of the original lever. And again that drops the force on the flapper to 67% of what it was with the original lever.

 

[skyrone]

so you would only lose 33 percent of your power. or tension to hold it closed.but as long as you had the extra travel i think you could adjust the wga so that its holds it shut well enough

 

[kenamond]

so you would only lose 33 percent of your power. or tension to hold it closed.but as long as you had the extra travel i think you could adjust the wga so that its holds it shut well enough

I forget what the stock vs. upgraded flapper size is on the evo3b16g, but if you can find that and compute the areas of both, that tells you roughly how much you can tolerate in decreasing the preload force on the flapper. The larger flapper apparently is prone to leak backpressure, so you could use that as a gauge of how much preload you can lose without the flapper leaking. But at the same time, that depends on the level of boost you're running. I'd guess that 33% loss might be too much. And then you still don't know if 45° is enough to stop creep.

 

[skyrone]

o yeah damn this is kinda shivvy... i thought that was for the ideal 90 10 degrees wouldnt do much at all i wonder if you can just buy wastegates somewhere. id rather get one with alot of travel and just find a way to make it fit

 

[Calan]

Before you worry about the WGA, disconnect the WGA rod from the flapper arm so that it's free to open on it's own, and see if you still creep.

If you do, opening the flapper further (with a new/modified WGA) isn't going to help it. (it may change spool up or other characteristics though, depending on preload, etc.). Besides that, if you didn't port the E16g on the backside of the flapper hinge (?), it won't open anywhere near 90*... more like 60*.

Here is the thread Kenamond was referring to about the Peeper's mod:

http://www.dsmtuners.com/forums/turbo-system-tech/267309-evo3-16g-boost-creep-solved.html

And here is the article on porting the E16g for boost creep, if you haven't seen it:

http://www.dsmtuners.com/forums/art...oler/186525-how-cure-boost-creep-porting.html

 

[JusMX141]

Here are the pics, as promised.

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I thought this was a T25 actuator, but I was mistaken...it's a universal Garrett actuator with the dual fittings on the head, and a threaded (adjustable) arm joined to a Mitsu arm. If you were to use a T25 actuator, it would work on the same principal....you simply wouldn't have the adjustable arm unless you used a threaded barrel adjuster and cut threads onto the wastegate arm.

 

[skyrone]

yeah i ported it so it will open to ninety. and it still creeps idk if i said that earlier or not. but i dont se how making the t25 actuator adjustable will help. the one i have now is adjustable i can either have it so it opens alot but doesnt seal or seals good and doesnt open alot. i need travel!! not adjustability. Does the t25 actuator have much more travel??

 

[skyrone]

and heres another thought. why is the wastegate arm even rigged up to an actuator? why can't it just be hooked up to a spring that pulls on it and when a certain amount of push on the flapper occurs it overcomes the resistance of the spring? that sounds like an easier idea to me. I know rigging it up would take a long time figuring out spring tensions and what not but i just think it might be easier.

 

[rich3389]

You can get a 34 mm flapper and port the wastegate openings to match that. I have that setup on my 16g and i have no creeping problems.

 

[JusMX141]

Does the t25 actuator have much more travel??

Yes....more than double the travel of an MHI turbo's actuator.

The adjustability is in place to add preload for running higher boost. On some vehicles (VW's in particular) you don't even use a boost controller to achieve a higher boost level.....the boost level is determined by the adjustability of the wastegate actuator.

By adding preload (to run higher boost) to the wastegate actuator, you're pulling the diaphragm inward and adding tension to the spring....and sacrificing the travel of the arm. If you want the flapper to open really far, you can't have much tension on the arm. It's how they work....you must choose one or the other, or go external.

 

[kenamond]

I've posted to a swarm of creep posts the past few days, so forgive me if I've already said this...I've read that the T25 WGA has a weaker spring than the evo3 WGA. Also, the backpressure is pretty close to blowing open the flapper even with the evo3 WGA, so this may be a problem if you try to use a T25 WGA to get longer throw.

It's just so frustrating that these WGAs are a super-simple piece and it would be trivial to make one that worked very well for the evo3 on our DSMs, but nobody makes one or nobody has found one from another turbo that will do the job. I started looking at McMaster Carr for pieces-parts to see if one could be made, but no luck yet. *sigh*

 

[skyrone]

Would it be possible to easily gut the 16g waste gate, steal the spring, put it in the t25 wastegate, and then throw it on the 16g?

 

[skyrone]

You can get a 34 mm flapper and port the wastegate openings to match that. I have that setup on my 16g and i have no creeping problems.

How do you install one of those? My flapper is just on the arm there isnt any obvious way to get it off without cutting it out.

 

[JusMX141]

Would it be possible to easily gut the 16g waste gate, steal the spring, put it in the t25 wastegate, and then throw it on the 16g?

We can't forget that you're looking to mod the knockoff version of the Mitsu actuator....the same unit that I blew the diaphragm apart in when I tested it with 25psi.

I don't think your suggestion is possible because you're talking about two completely different springs in two completely different canisters.

At this point, you may want to start looking into a stronger actuator; perhaps modding an 18psi Evo actuator to fit:
Forced Performance: FP EVO 18PSI HP Wastegate Actuator

It appears that the Evo actuator has a much longer chamber, which would signify a longer throw....it also would have more spring tension; meaning more resistance to flapper blow-open- and it absolutely would NOT move until it saw 18psi.

 

[rich3389]

To get the flapper on, you need to have the turbo off the car, take off the 02 housing, and you will see the flapper.
What I did to get it off was using a dremel and a cutting disk, and cut the back of the flapper door where it is pressed onto the arm, then it popped right off. Putting the new one on is easy, stick the nipple through the hole, and use a punch and a big hammer and squash down the nipple.