External Wastegate Needed??? [Archive] - TriStateTuners.com

WRXtoS4

11-16-2005, 06:26 PM

Ok so here is the deal. I have a TXS Stage 4(vf-34) and lately have been having a real big problem holding boost levels. The car has also been having really really bad wastegate flutter, even only at 10 pounds of boost.

I think the solution would be to upgrade to a Tial External WG but dont want to go through the hassle if that is not the problem. If you think this is the route to go, please let me know, and if anyone has the Tial WG, let me know if you like it or not.

Thanks guys.

joe tom

11-16-2005, 07:41 PM

koho2731

11-16-2005, 07:50 PM

I have a Tial 38mm and I have no creep or flucuation. Yes I know it's a diff application, but external WG usually solve most flucuation and creep problems. I'd do a boost lk ck first before I spent any money on parts

TurboTagTeam

11-16-2005, 08:59 PM

I'm no expert on subaru's but, If you switched to an external wastegate wouldn't you have to get a whole new exhaust mani that made for an external WG? That would be pretty expensive. Are you using a MBC? If you are that could be it too.

teh DIRT

11-16-2005, 09:01 PM

you would really just need to have a wastegate welded onto the uppipe

2point4DSM

11-16-2005, 09:41 PM

Ok so here is the deal. I have a TXS Stage 4(vf-34) and lately have been having a real big problem holding boost levels. The car has also been having really really bad wastegate flutter, even only at 10 pounds of boost.

What is wastegate flutter and how is it not holding boost levels? Do you mean it spikes and then drops or it hits boost and then creeps. Only flutter I know about is BOV flutter. Or when the BOV isn't working at all and the turbo makes noises as boost tries to spin it backwards.

I've got a Tial 46mm. Tials with 4 bolts are awesome... except when they come with the wrong spring and then not loctite the bolts putting it back together, lol. Tials with 2 bolts holding it to the up-pipe, manifold are very prone to leaking due to the movement of the piece blowing out the gasket.

teh DIRT

11-16-2005, 09:49 PM

wastegate flutter on scoobies is the wastegate opening slightly and closing over and over...like its not sure what to do lol/

2point4DSM

11-16-2005, 10:04 PM

wastegate flutter on scoobies is the wastegate opening slightly and closing over and over...like its not sure what to do lol/

So does that mean your boost goes up and down, up and down, etc, through a gear?

Could it be that the wastegate actuator isn't seeing a stable boost/vacuum source. Does taking the reading from another source alleviate the symptoms. DSMs usually run a line from the intake manifold or from really close to the turbo itself.

Still this doesn't really make sense to me if a different spring is suppose to fix this. A weak spring to me seems like it would cause boost to be limited to a certain level.

When DSMrs swap the wastegate flapper on certain turbos the wastegate actuator starts to get overpowered and exhaust leaks out the wastegate limiting boost. One possible solution is to add washers btw the actuator and the mounting point to pull it further away and thus increasing spring tension. Or increasing the exhaust flow better so that there is less backpressure pushing on the wastegate flapper.

koho2731

11-16-2005, 11:02 PM

What is wastegate flutter and how is it not holding boost levels? Do you mean it spikes and then drops or it hits boost and then creeps. Only flutter I know about is BOV flutter. Or when the BOV isn't working at all and the turbo makes noises as boost tries to spin it backwards.

I've got a Tial 46mm. Tials with 4 bolts are awesome... except when they come with the wrong spring and then not loctite the bolts putting it back together, lol. Tials with 2 bolts holding it to the up-pipe, manifold are very prone to leaking due to the movement of the piece blowing out the gasket.
That is why you don't use a gasket (if the sufaces are mach.) and use lock washers to keep the bolts from backing out

Chair-Force

11-16-2005, 11:06 PM

my wastegate flutters like crazy too (vf34), i heard that there is a "wastegate spring" that will fix this, but i have yet to find where to get one of these springs, or how to install one.

2x, my boost (vf34) is the fluttermaster

TROLL

11-16-2005, 11:18 PM

yeah if it flutters thats not necessarily a problem, if its not holding boost then that of course is a problem. however you definitely do not need an external wastegate... i'm sure the problem is elsewhere. if you want i can check it out one day... cant make any promises that i'll find anything but its worth a look.
bryan

joe tom

11-16-2005, 11:24 PM

WRXtoS4

11-16-2005, 11:36 PM

I am down for that Brian. I need some help soon. Its not even fun to drive this car anymore.

TROLL

11-16-2005, 11:41 PM

[subtle hint]I'm not just the resident VF34 mechanic, I'm a very near future member![/subtle hint]

WRXtoS4

11-16-2005, 11:50 PM

Holy Crap!! Welcome to the club LOL

wgknestrick

11-16-2005, 11:53 PM

This problem isn't usually related to the wastegate itself, but to the method of boost controll. What method are you using?

If you are contemplating EWG, you should also be contemplating a new turbo. Putting a EWG on a VF series turbo just doesn't make any $ sense.

2point4DSM

11-17-2005, 01:47 AM

Putting a EWG on a VF series turbo just doesn't make any $ sense.

Very possible to just weld the flapper arm in the closed position and then mount the external gate closer to the head.

This use to be the way to go with DSMs back in the day.

Btw, where do you guys tap your boost/vacuum source for so many people to be having the same issue.

joe tom

11-17-2005, 08:39 AM

[subtle hint]I'm not just the resident VF34 mechanic, I'm a very near future member![/subtle hint]

noice!

sur4die

11-17-2005, 09:29 AM

does the VF34 have an adjustable WG arm length like the TD04H? my stocker would flutter quite loudly, but once i shortened the arm a by a turn or two it went away.

i can remember mine doing this even on stock engine management. once i got a catless exhaust in it i could hear EVERYTHING that was happening with the impellar/WG.

it sounds like an angry swarm of locusts :devil: i love it! :inlove:

joe tom

11-17-2005, 09:56 AM

does the VF34 have an adjustable WG arm length like the TD04H? my stocker would flutter quite loudly, but once i shortened the arm a by a turn or two it went away.

unfortunately the vf series doesn't have an adjustable WG arm, i looked into this also.

TehWagon

11-17-2005, 10:01 AM

can someone give a brief (and simple) explanation of why the EWG is mounted to the uppipe? this makes no sense to me.

also, bill - what is the reason that an EWG + a VF34 don't mix?

i don't think it'll take it ot to answer... i think it'll be informative for the thread... thx.

teh DIRT

11-17-2005, 10:27 AM

a wastegates purpose it to let exhaust gases entering the turbo leave the exhaust path therefore never reaching the turbo and spinning the turbine. Therefore a wastegate needs to be placed in the exhaust stream before the turbo. The up-pipe is a suitable place for this

2point4DSM

11-17-2005, 10:31 AM

can someone give a brief (and simple) explanation of why the EWG is mounted to the uppipe? this makes no sense to me.

Because it is pre-turbo. The purpose of a wastegate is to bypass the flow of exhaust (from the motor) so that the turbo doesn't spin any faster.

Turbos produce boost when exhaust hits the turbine wheel (turbo wheel on the exhaust side) and spins it which is connected by a shaft to the compressor wheel (turbo wheel on the intake filter side). A certain size turbo will produce a certain amount of boost for a given motor at a certain turbo rpm. The wastegate's function is to allow exhaust to hit the turbine wheel till it reaches a predetermined amount of boost and then opens so it doesn't spin anyfaster.

2point4DSM

11-17-2005, 10:34 AM

also, bill - what is the reason that an EWG + a VF34 don't mix?

I believe Bill's point is just monetary considerations. You can stick an EWG on any turbo setup. But when the stock internal gate is more than sufficient to flow the air then why bother.

2point4DSM

11-17-2005, 10:46 AM

Why EWG?

Certain turbo shops are able to put together frankenstein type turbos. Meaning they mix and match parts from one manufacturer to another. The reason they do this most often is because exhaust manifolds, o2 housings and downpipes are unique from one motor to another. And since most people are just looking to upgrade a turbo and not all those other pieces then it becomes cost efficient to mate a bigger compressor wheel to the stock turbo by cutting out the compressor cover to fit.

A bigger compressor wheel allows a turbo to produce more boost which the stockish exhaust side (internal gate) might not be able to compensate for because of its size. That is the reason for going with an EWG that comes in different sizes.

TehWagon

11-17-2005, 10:58 AM

thanks for the info- i think seneca needs to pipe in here... i seem to remember him thinking that EWG's made sense for any setup... :confused:

teh DIRT

11-17-2005, 10:59 AM

http://forum.jaas.de/images/smiles/icon_smokin.gif

senecas EWG sounds like god is emerging from the turbine side of his turbo.

seneca

11-17-2005, 11:09 AM

ask kingpin how much power they made on a stock turbo sti with only the addition of an EWG and well see whos smoking it. The ewg controlled boost spikes better than the stock gate and effectively increased the flow of the hotside thus reducing egbp's.

teh DIRT

11-17-2005, 11:12 AM

im with seneca on this one, the EWG is much more precise

2point4DSM

11-17-2005, 11:17 AM

External gates definitely react a little faster and help control boost a lot. But an electronic controller on a well setup stockish internal gate should work similar.

And if the external gate is dumped right back into the exhaust like the stockish setup then there should be very little gained, if any. Of course dumping the external to atmosphere has been known to gain around 30hp on DSMs as well.

Any of you guys remember/know the stockish black DSM with 250k on the odo that raced blue32. All he has is a muffler, K&N intake and an external dumping o2 housing running off the stock internal gate.

teh DIRT

11-17-2005, 11:19 AM

yeah the r32 owned.

okay maybe owned isnt the right word.

2point4DSM

11-17-2005, 11:20 AM

Yes he did, lol. But instead of 10 car lengths it was just a few, lol.

Btw, I'm running a 46mm tial on mine so there is no need to convince me, lol. I'm just going off prior experiences considering I've been through roughly a dozen turbos. I've had them ported, internal gates enlarged, springs tightened, external gate on the manifold, external gate on the o2 housing, etc., etc. And I'm usually the guy that is promoting ewg. Just this time I felt like being devil's advocate, lol.

seneca

11-17-2005, 11:20 AM

egbp = exhaust gas back pressure in case anyone wants to comment on that.

2point4DSM

11-17-2005, 11:28 AM

Btw, I use to have a delta gate which is probably a 32-38mm wastgate (I forget). The Tial 46mm is a lot quieter, surprisingly. It would seem that a bigger unit would be louder like having a bigger exhaust. But that is not the case.

seneca

11-17-2005, 11:30 AM

my 44mm is insanely loud.

teh DIRT

11-17-2005, 11:30 AM

my 44mm is insanely loud.

sure is.

2point4DSM

11-17-2005, 11:37 AM

Is it insanely loud like the black DSM that ran Blue32 who is running a 26mm or is it insanely loud like my 46mm. I'm guessing somewhere in btw. Most people say the 26mm is just plain obnoxious, lol.

TehWagon

11-17-2005, 11:44 AM

thanks sen i was just about to ax what egbp was...

physically it makes sense that a smaller mm ewg would be louder- more air going thru, like a whistle... increase the size, less air heard...

SpendOne

11-17-2005, 11:46 AM

egbp = exhaust gas back pressure in case anyone wants to comment on that.

Back pressure??? You dont need back pressure on a turbo car.

SpendOne

11-17-2005, 11:47 AM

I dont think my 38mm is loud, but tahts probably cause I got used to it. When my buddies are in teh next car over they say I make them go deaf. I do remember when I first threw it on. You could hear my car about 3-4 blocks away.

TehWagon

11-17-2005, 11:47 AM

that's what he was saying- it eliminated that...

2point4DSM

11-17-2005, 11:51 AM

I do remember when I first threw it on. You could hear my car about 3-4 blocks away.

That hasn't changed, lol.

2point4DSM

11-17-2005, 11:53 AM

Back pressure??? You dont need back pressure on a turbo car.

Yes you do. Just that the turbo acts as the major source of backpressure.

Stick a bigger turbine housing on there (less backpressure) and notice how the motor all of a sudden feels a lot more laggy.

SpendOne

11-17-2005, 12:26 PM

That hasn't changed, lol.

I dont think its that loud in my true honest opinion...Oh yea anwser your phone!

2point4DSM

11-17-2005, 01:11 PM

Best thing about running an external dump is that it's like running with a testpipe only at full boost.

wgknestrick

11-17-2005, 01:50 PM

My point on why a VF turbo and an external WG doesn't make much sense is this. You will have almost $1K just in the wastegate/tubing. Noting the vf series unstellar performance, low eff, and goofy flange, it doesn't make much sense to put one back on. Since you are spending money on all these other parts, I would do it once, and do it right. Put a true GT30R in place of that tiny vf34.

2point4DSM

11-17-2005, 02:29 PM

Noting the vf series unstellar performance.... Put a true GT30R in place of that tiny vf34.

Bigger is always better, lol.

seneca

11-17-2005, 03:09 PM

I wouldnt say an ewg eliminate egbp but since subys seem to have more of an issue with pre turbine backpressure due to the length of our headers it surely helps. heat and gas velocity loss is a bich isnt it. wrap it up B.

TehWagon

11-17-2005, 03:18 PM

ok your word was 'reducing'... my bad...

WRXtoS4

11-17-2005, 04:10 PM

Well I cant put a GT30 on because I dont have time or money.

Here is my deal.

I cant stand it when your car is running great at one point in time, and then all the sudden your car is running like crap. When I first got the car I loved it, but it is just not the same ride anymore. I barely have to step on the gas anymore for the wastegate to start going crazy, which is why I thought the solution would be to get rid of the wastegate. So I guess my next question is if I shouldnt change the wastegate, what is the next solution?

TehWagon

11-17-2005, 04:13 PM

sounds like there was mention of mbc's in here as well... might want to try a $40 part to see if it fixes the problem before you go too 'bling' :)

seneca

11-17-2005, 04:21 PM

Ill be parting out my sti if I cant find a buyer for it as is. SR55/44MM/eboost will all be ont he chopping blocks.

WRXtoS4

11-17-2005, 04:22 PM

I have the HP Turbo XS Boost Controller on their right now.

sur4die

11-17-2005, 04:46 PM

why don't you try placing some washers in the waste gate actuator mounting bracket in an attempt to move the waste gate actuator further from waste gate, effectively shortening the actuator arm length. that should help with your low boost levels and flutter.

edit: wait, you have an MBC? did you happen to take the "restrictor" bead out of the controllers boost sense line? that would definately roughen up your boost controller/waste gate response.

2point4DSM

11-17-2005, 08:50 PM

One possible solution is to add washers btw the actuator and the mounting point to pull it further away and thus increasing spring tension.

Post #8.

TehWagon

11-17-2005, 08:54 PM

heh... good ideas guys :) let us know how it works out for you, redscooby!

sur4die

11-18-2005, 01:04 AM

Post #8.

and that's why i shouldn't post to 3 page long threads...

2point4DSM

11-18-2005, 08:30 AM

Actually, I'm glad you did cause I was starting to get the impression that it was over-looked and was going to mention it again, lol.

wgknestrick

11-18-2005, 09:03 AM

The "helper" spring is much easier mod to do. Get a spring from a hardware store that you can stretch over the WG lever and attach it to the OEM spring housing. It will only cost you about 1hr and $10 to try this.

It also could be your BOV causing compressor surge when you let off the gas. I've seen a ton of people with an aftermarket BOV not setup properly and then complain about WG "flutter"

WG flutter should only happen ON boost when you are accelerating. IE the WG is fuctioning.

Bill