Turbo Boost Creep Creeping T25 14B 16G [Merged]

[forcefed86]

You need more back pressure, post 02 housing, or a bigger wastegate (external) but that's a bit more custom work than just adding a cat or smaller DP. You could also have two exhaust systems by using an electric cutout. So one exhaust to control boost and be quite then flip a switch and bam 3" straight pipe max boost (tune for it of course) Watch out for knock, the 16g starts blowing hot air on the higher boost levels and pump gas won't cut it.

I ran 25 psi on my 16g pump gas all day long with nothing more than a chip and 91 octane. I can't see restricting the exhaust as a valid method or reducing boost. It destroys power and puts tons of heat into all the parts.

 

[Paintballaa5]

You need more back pressure, post 02 housing, or a bigger wastegate (external) but that's a bit more custom work than just adding a cat or smaller DP. You could also have two exhaust systems by using an electric cutout. So one exhaust to control boost and be quite then flip a switch and bam 3" straight pipe max boost (tune for it of course) Watch out for knock, the 16g starts blowing hot air on the higher boost levels and pump gas won't cut it.

I have a 3" cutout, with the stock muffler on the back. So when closed, it should have plenty of restriction, but it still does it then. It's completely ported, and worked just fine before.

What I've tried so far:

1) Disconnected actuator arm from flapper and it still creeped.
2) Stock muffler doesn't solve the problem.
3) Checked all lines to boost controller, and the controller itself.
4) Took out the controller and ran line from wastegate to j-pipe.

 

[NHerron]

I meant if it creeps enough (past 25) watch out. Thats out the efficiency range and not worth the trouble anyway unless trying for a record, and thats different fueling to combat knock.

Adding a cat will not destroy power. Neither will a smaller dp. It's just enough to prevent creep but not effect power noticably. A different housing might do it too, I couldn't remember what hes running, figured it was stock

 

[Paintballaa5]

I just need to know if there are any other tests I should try, or any other parts that could affect this? I feel like i've done everything.

The only thing that changed since it started creeping was the 3" cutout, with the stock muffler on the back.
Before it just had a regular ole' 3" muffler. But since the stock muffler is more of a restriction than the 3" I can rule out the exhaust, correct?

 

[forcefed86]

I meant if it creeps enough (past 25) watch out. Thats out the efficiency range and not worth the trouble anyway unless trying for a record, and thats different fueling to combat knock.

Adding a cat will not destroy power. Neither will a smaller dp. It's just enough to prevent creep but not effect power noticably. A different housing might do it too, I couldn't remember what hes running, figured it was stock

Thats total BS, your essentially bottle necking the system. There is to much pressure in the exhaust pre-turbo to keep boost under the desired PSI with the OEM exhust housing.

Restricting this with anything post turbo will hurt power and cause excessive heat buildup. Especially with "cats." Running a larger turbo housing is the proper way to fix the "problem."

My 16G loved higher boost pressures. It lasted a long time as well. After I sold it it went on to set a 16g record in kevins RWD talon.

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[Paintballaa5]

I don't plan on putting a restrictor in. It doesn't have anything to do with the exhaust being to free flowing. It still creeps on the stock muffler.

 

[NHerron]

Look forcefed the fact is putting in a high flow cat or something to that effect will usually help keeo creep at bay. I am aware its not the ideal solution in technical terms, the wastegate needs to be a larger total area to discharge higher exhaust volume than its design because the wastegates' limit has been reahed and consequently cannot control boost anymore. A bigger housing will not fix it, the problem is before the housing- the exhaust don't want to take a sharp 90 and exit through a tiny hole compared to the turbines exit. Porting this hole and smoothing out the turn will help, if not, time to go external. But how much money and work is that compared to slapping in a high flow 3"cat. Once again if you want to be technical, yes, a cat will technically hurt performance. Its not going to be a noticable difference though. Here's a good read.

http://www.dsmtuners.com/forums/newbie-forum/288456-oversized-exhaust-boost-creep-rationale.html

To the OP, it goes 3" dp, 3" side cutout then stock exhaust after?

 

[forcefed86]

Look forcefed the fact is putting in a high flow cat or something to that effect will usually help keeo creep at bay. I am aware its not the ideal solution in technical terms, the wastegate needs to be a larger total area to discharge higher exhaust volume than its design because the wastegates' limit has been reahed and consequently cannot control boost anymore. A bigger housing will not fix it, the problem is before the housing- the exhaust don't want to take a sharp 90 and exit through a tiny hole compared to the turbines exit. Porting this hole and smoothing out the turn will help, if not, time to go external. But how much money and work is that compared to slapping in a high flow 3"cat. Once again if you want to be technical, yes, a cat will technically hurt performance. Its not going to be a noticable difference though. Here's a good read.

http://www.dsmtuners.com/forums/newbie-forum/288456-oversized-exhaust-boost-creep-rationale.html

To the OP, it goes 3" dp, 3" side cutout then stock exhaust after?

That seems like a backassed way of doing things IMO. The whole point of a turbo is to turn exh energy into power. So lets run a tiny ass turbo and a huge wastegate and piss all the power out the wg? Or bottleneck the hell out of the already ineffecient tiny turbo with exhaust restrictions?

To the OP.

You can't go swapping out aftermarket parts and expect the car to function like an OEM setup. From my experience. If you have a huge aftermarket down pipe you will see creep regardless of what muffler is on the ass end of your exhaust system. I was able to tame my car down to 9-10lbs using 100% non ported all original e316g (no ported wg) using a 2.5"downpipe and 2.5" exhaust (no cats) through a magnaflow 3" turbo muffler. That's the same setup you see making over 35 psi in the video above. Local friend has the same setup and a 3" down pipe w/ 3" exh and it would creep to the 20's like you are seeing.

If what your saying is true it makes no sense. If the only change was the addition of a 3" Y after the same downpipe U were running earlier this would not cause boost creep. If you didn't have it before you shouldn't now. something else had to of changed. Do you have the WGA shimmed? Are you sure it's opening 100% and not just cracking a tad? Have you tried bypassing the BC and running a vac line straight fromt eh turbo to the WGA? Are you sure the WGA is not damaged? Bent arm etc?

 

[Paintballaa5]

If what your saying is true it makes no sense. If the only change was the addition of a 3” Y after the same downpipe U were running earlier this would not cause boost creep. If you didn’t have it before you shouldn’t now. something else had to of changed. Do you have the WGA shimmed? Are you sure it’s opening 100% and not just cracking a tad? Have you tried bypassing the BC and running a vac line straight fromt eh turbo to the WGA? Are you sure the WGA is not damaged? Bent arm etc?

I have run a line straight from the j-pipe to the WGA. Also, I disconnected the arm from the flapper, and it still crept, which should rule out a torn diaphragm.

I know, it makes absolutely no sense, thats why I cannot come to a conclusion on this.

 

[NHerron]

Another thing to do is seafoam.... with engine running, suck up half a can via brake booster then shut off engine. Start it up after 30mins or so and pay attention to the o2, dp, and basically anywhere before the stock sized section

 

[gofer]

That seems like a backassed way of doing things IMO. The whole point of a turbo is to turn exh energy into power. So lets run a tiny ass turbo and a huge wastegate and piss all the power out the wg?

You need to research how a wastegate works because if anything that's been posted in this thread is assbackward's it's that statement.

Exhaust will flow like water, taking the path of least resistance. If the path of least resistance is across the turbine (exhaust wheel of the turbo) the turbo will continue to build boost. You may have installed the stock muffler but the restriction isn't close enough to the turbo to make any difference.

How big is the downpipe you installed with the cutout on it?

Do you have a catalytic converter?

What o2 housing do you have?

 

[Paintballaa5]

Exhaust will flow like water, taking the path of least resistance. If the path of least resistance is across the turbine (exhaust wheel of the turbo) the turbo will continue to build boost. You may have installed the stock muffler but the restriction isn't close enough to the turbo to make any difference.

How big is the downpipe you installed with the cutout on it?

Do you have a catalytic converter?

What o2 housing do you have?

Right I get how it flows across the turbine, but I don't get why the stock muffler with more restriction, would creep, but the 3" muffler on before wouldn't. Thats what stumps me.. There's bound to be something I'm missing here since it worked before..

It's a 2.5-3" downpipe, with the piping and cutout 3" all the way to the stock muffler.

No cat

Stock o2 housing, put its been hogged out.


By the way, thank you for all yall's help so far. 'preciate it!

 

[gofer]

Just so I can get this straight.

Setup before boost creep: Hogged out 2g o2 housing - 2.5" to flex 3" downpipe - no cat - 3" exhaust with a 3" muffler

Setup after boost creep: Hogged out 2g o2 housing - 2.5" to flex 3" downpipe with cut out - no cat - 3" exhaust with a stock muffler​

Where in the dp did you install the cutout?

My best guess, keep in mind I'm no engineer and have a high school diploma thumb, is that the cut-off, even though it's closed, is creating the boost creep issue you're seeing. For whatever reason the exhaust isn't wanting to re-route through the wastegate path and I'm going to say it's because of the turbulence in the dp that you created by installing the cut-out. Somehow, someway, I guess it's possible that the flapper isn't moving freely. When you pulled the wga off of it did you attempt to swing it side to side with your hand?

I had boost creep issues and my fix was going to a PR o2 and external wastegate setup which was overkill. Just getting an externally dumped o2, that still uses the stock wga, is enough since the exhaust exit for the wastegate is to atmosphere and "the path of least resistance." Unfortunately this kills the sleeper appearance it seems you're trying to achieve but, like a wiseman once said, "Boost Creep is your turbo's way of calling you a little bi*** for not running enough boost." Kidding of course.

I drew this back in the day, just pulling it out for reference so you can get an idea of what I mean by turbulent exhaust.

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PR makes a nice o2 dump, getting it coated black (or painting it Rust-O-Leum BBQ black) would make it go un-noticed, but it's just a suggestion. PUNISHMENT RACING STAINLESS STEEL ATMOSPHERE VENTED O2 HOUSING

 

[forcefed86]

You need to research how a wastegate works because if anything that's been posted in this thread is assbackward's it's that statement.

Exhaust will flow like water, taking the path of least resistance. If the path of least resistance is across the turbine (exhaust wheel of the turbo) the turbo will continue to build boost. You may have installed the stock muffler but the restriction isn't close enough to the turbo to make any difference.

How big is the downpipe you installed with the cutout on it?

Do you have a catalytic converter?

What o2 housing do you have?

What are you trying to point out? The statement I made makes perfect sense. It was an example of how most tiny turbo dsm guys setup there turbo systems. It's a waste of exh. energy to dump it all out the WG. That's all that statement meant. It has nothing to do with flow resistance characteristics.

Also Pre-turbo is a pressure system. It doesn't "flow like water", it's under pressure from every angle. The exhaust doesn't ignore the WG hole if the turbine inlet is providing less resistance. It will still vent out pressure if the WG hole is open. It doesn't not bypass it. It's more like a balloon full of air. A hole anywhere in the system will vent out pressure regardless.

To the OP. So you've ruled out the WGA. You still didn't say if you had it shimmed. Have you physically checked the pucks travel distance? Is it opening completely?

 

[Paintballaa5]

Just so I can get this straight.

Setup before boost creep: Hogged out 2g o2 housing - 2.5" to flex 3" downpipe - no cat - 3" exhaust with a 3" muffler

Setup after boost creep: Hogged out 2g o2 housing - 2.5" to flex 3" downpipe with cut out - no cat - 3" exhaust with a stock muffler​

Where in the dp did you install the cutout?

My best guess, keep in mind I'm no engineer and have a high school diploma thumb, is that the cut-off, even though it's closed, is creating the boost creep issue you're seeing. For whatever reason the exhaust isn't wanting to re-route through the wastegate path and I'm going to say it's because of the turbulence in the dp that you created by installing the cut-out. Somehow, someway, I guess it's possible that the flapper isn't moving freely. When you pulled the wga off of it did you attempt to swing it side to side with your hand?

I had boost creep issues and my fix was going to a PR o2 and external wastegate setup which was overkill. Just getting an externally dumped o2, that still uses the stock wga, is enough since the exhaust exit for the wastegate is to atmosphere and "the path of least resistance." Unfortunately this kills the sleeper appearance it seems you're trying to achieve but, like a wiseman once said, "Boost Creep is your turbo's way of calling you a little bi*** for not running enough boost." Kidding of course.

Yes sir, that is my exact setup. It is positioned about a foot from the end of the cat-less dp. Pic below:

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I see what you mean. The gasses are trying to go out of the y section but can't, so they reverse out and disrupt the flow going to the back, causing turbulence correct? That makes perfect sense. It's a longshot, but hey, I'm willing to try anything at this point.

And yes, the flapper moved freely, I inspected it as best i could without pulling the turbo, and nothing seemed out of place.

I also feel like an external wg would be overkill for a 16g.

 

[gofer]

What are you trying to point out? The statement I made makes perfect sense. It was an example of how most tiny turbo dsm guys setup there turbo systems. It's a waste of exh. energy to dump it all out the WG. That's all that statement meant. It has nothing to do with flow resistance characteristics.

It makes no sense, please explain how running an external wastegate "pisses" away all the power if you're running a small turbo?

Exhaust gases to do take the path of least resistance, if there is a lower pressure drop across the turbine than the wastegate port guess where the majority of the exhaust is going to go? Since you're referencing a balloon(?), take a needle and stab a pin hole in the side of your balloon and then open up the neck of it, where you blow air in, and the air is going to take the path of least resistance out of the neck 10 times out of 10.

 

[Paintballaa5]

Well I'll be heading down to the muffler shop here pretty soon. (I'm trying to get it ready for the local drag night Saturday) I'll let ya know how the turbulence theory works out.

Thanks for all your help Corey!
-Logan

 

[forcefed86]

It makes no sense, please explain how running an external wastegate "pisses" away all the power if you're running a small turbo?

Exhaust gases to do take the path of least resistance, if there is a lower pressure drop across the turbine than the wastegate port guess where the majority of the exhaust is going to go? Since you're referencing a balloon(?), take a needle and stab a pin hole in the side of your balloon and then open up the neck of it, where you blow air in, and the air is going to take the path of least resistance out of the neck 10 times out of 10.

Of course it makes sense. Any exhaust that is directed out of your exhaust system before it enters the turbo is energy being wasted. Thats why the freeking thing is called a WASTE gate! And it would be more efficient to run a larger turbine and not waste all that exhaust energy out of the waste gate.

I never said it didn't take the path of least resistance I said it doesn't flow like water. Big difference. If you took a needle and poked a hole in a balloon and opened the neck you would still get pressure out the pin hole. The air would NOT bypass the pin hole.

 

[gofer]

Of course it makes sense. Any exhaust that is directed out of your exhaust system before it enters the turbo is energy being wasted.

How is running a bigger wastegate going to direct more exhaust out of the exhaust system before it enters the turbo and waste energy forcefed?

The wastegate size has nothing to do with turbine efficiency or power. The more boost that's run the less exhaust will be bypassed because the turbo is requiring more exhaust flow across the turbine and vise-versa.

The amount of boost on the cold side of the turbo is what regulates the opening/closing of the wastegate, which is why there's a vacuum line attached to it. Running a bigger wastegate just means that it doesn't have to open as far off of its seat to maintain proper pressure over the turbine wheel (boost pressure in the charge pipes). The bigger wastegate isn't going to "waste" anymore exhaust energy than a smaller wastegate trying to achieve the same boost pressure, it just doesn't work like that. Now, it is possible that the bigger wastegate port (more surface area) could potentially blow open trying to achieve a higher boost pressure but we're talking about boost creep which is something entirely different.

I never said it didn't take the path of least resistance I said it doesn't flow like water. Big difference. If you took a needle and poked a hole in a balloon and opened the neck you would still get pressure out the pin hole. The air would NOT bypass the pin hole.

...and neither would water or exhaust gases. Since you're sticking to your guns on balloon theory, rather than filling the balloon with air fill it with water and do the same. Water and air BOTH take the path of least resistance sir, resistance being the high pressure of the pin hole in the balloon and the low pressure being the neck of it. In a properly working wastegate setup the wastegate controls where the low pressure is, whether it's over the turbine wheel or out the wastegate port, to achieve the set amount of boost.

 

[forcefed86]

How is running a bigger wastegate going to direct more exhaust out of the exhaust system before it enters the turbo and waste energy forcefed? The wastegate size has nothing to do with turbine efficiency or power. The more boost that's run the less exhaust will be bypassed because the turbo is requiring more exhaust flow across the turbine and vise-versa.

You are totally wrong! If the WG hole is too small or the turbine housing is too small (like the 16g!) then the WG will never close completely. That is why we see Exh/intake pressure ratios of 3:1+ on these engines running high boost with 14b 16g etc. That is exactly why a small turbo is inefficient. A very efficient turbo setup would have 1:1 Exh/int pressure ratio or better! This also creates lag which is why we run smaller housings and WG's in the first place. You have to find a happy median between lag and efficiency.

The amount of boost on the cold side of the turbo is what regulates the opening/closing of the wastegate, which is why there's a vacuum line attached to it. Running a bigger wastegate just means that it doesn't have to open as far off of its seat to maintain proper pressure over the turbine wheel (boost pressure in the charge pipes). The bigger wastegate isn't going to "waste" anymore exhaust energy than a smaller wastegate trying to achieve the same boost pressure, it just doesn't work like that. Now, it is possible that the bigger wastegate port (more surface area) could potentially blow open trying to achieve a higher boost pressure but we're talking about boost creep which is something entirely different.

Wrong... again.

First, regardless of where the WG port is there are 2 forces working it. With a tiny 16g exh housing at high boost the exh pressure on the opposite end of the puck alone is enough to open it. (esp. if there is a larger aftermarket puck) it can easily overpower the stock WGA completely.

The 16g gate is not large enough to keep the boost at the desired level for the OP. The WG is being overrun when the gate is wide open. That is why when the OP detached the WG arm the turbo still over-boosted. The WG hole isn't physically large enough to keep the boost in check with that tiny housing. Now take a turbo with a larger exhaust wheel and hotside and install it. (say a 12cm HX35) Run an equivalent internal gate setup to the 16g and it will be able to keep boost in check because the turbine drive pressure has lowered with the larger housing. In addition instead of the exhaust being wasted it is used to drive a larger turbo wheel thus converting that exh energy that was previously wasted into power. Or run a larger gate and piss away the exh pressure that could be used to make more power.

...and neither would water or exhaust gases. Since you're sticking to your guns on balloon theory, rather than filling the balloon with air fill it with water and do the same. Water and air BOTH take the path of least resistance sir, resistance being the high pressure of the pin hole in the balloon and the low pressure being the neck of it. In a properly working wastegate setup the wastegate controls where the low pressure is, whether it's over the turbine wheel or out the wastegate port, to achieve the set amount of boost.

No, I said regardless of what you fill it with water/air will still come out the pin hole, it will not bypass the smaller hole and all flow out the larger one. We aren't talking pin holes with a turbo/WG either. The key phrase here is "properly working". That would assume the WG could bypass enough exh. to keep boost at the desired level with the size turbine being used. It isn't on a 16g!

 

[gofer]

You are totally wrong! If the WG hole is too small or the turbine housing is too small (like the 16g!) then the WG will never close completely. That is why we see Exh/intake pressure ratios of 3:1+ on these engines running high boost with 14b 16g etc. That is exactly why a small turbo is inefficient. A very efficient turbo setup would have 1:1 Exh/int pressure ratio or better! This also creates lag which is why we run smaller housings and WG’s in the first place. You have to find a happy median between lag and efficiency.

I'm not quiet understanding what you're trying to say about the wg port never closing completely from it being too small? I do agree that using a small A/R turbine housing will increase exhaust gas velocity across the turbine as well as increase exhaust back pressure, which is what I think you're trying to say?

Wrong… again.

First, regardless of where the WG port is there are 2 forces working it. With a tiny 16g exh housing at high boost the exh pressure on the opposite end of the puck alone is enough to open it. (esp. if there is a larger aftermarket puck) it can easily overpower the stock WGA completely.

What are the two forces working the WG port?

You're telling me that I'm wrong and at the same time you're agreeing with what I had previously posted, quoted in bold below. We're not talking about high boost though because, if we were, boost creep wouldn't be the issue...

Now, it is possible that the bigger wastegate port (more surface area) could potentially blow open trying to achieve a higher boost pressure...​

The 16g gate is not large enough to keep the boost at the desired level for the OP. The WG is being overrun when the gate is wide open. That is why when the OP detached the WG arm the turbo still over-boosted. The WG hole isn’t physically large enough to keep the boost in check with that tiny housing.

Once again, you're saying I'm incorrect yet agreeing with what I'm saying in your statement, see bolded quote below.

Exhaust will flow like water, taking the path of least resistance. If the path of least resistance is across the turbine (exhaust wheel of the turbo) the turbo will continue to build boost.​

Now take a turbo with a larger exhaust wheel and hotside and install it. (say a 12cm HX35) Run an equivalent internal gate setup to the 16g and it will be able to keep boost in check because the turbine drive pressure has lowered with the larger housing. In addition instead of the exhaust being wasted it is used to drive a larger turbo wheel thus converting that exh energy that was previously wasted into power. Or run a larger gate and piss away the exh pressure that could be used to make more power.

Maybe I'm misunderstanding you correctly because board communication can be a bit tough at times.

Assume you're running an HX35 in the .55 A/R BEP housing and you've got two wastegates, one's a MV-S (38mm) and the other is a MV-R (44mm) both using the same 1BAR spring. From what you're telling us that by installing the bigger MV-R wastegate you'll waste more exhaust gas and the turbo won't spool as efficiently and power output will be less?

You are correct, the bigger turbine housing (A/R) and turbine wheel will definitely lower exhaust gas velocity across it and effectively lower backpressure while doing so but, again, what does the size of the wastegate have anything to do with power output? Nothing.

No, I said regardless of what you fill it with water/air will still come out the pin hole, it will not bypass the smaller hole and all flow out the larger one. We aren’t talking pin holes with a turbo/WG either. The key phrase here is “properly working”. That would assume the WG could bypass enough exh. to keep boost at the desired level with the size turbine being used. It isn’t on a 16g!

Again, you're disagreeing with me and then typing it up to say the same thing I just said.

 

[forcefed86]

The problem is you don't see a difference between what I said and what you said, I do.

I'm not quiet understanding what you're trying to say about the wg port never closing completely from it being too small? I do agree that using a small A/R turbine housing will increase exhaust gas velocity across the turbine as well as increase exhaust back pressure, which is what I think you're trying to say?:

I didn't try to say that, I did say that. In addition to that statement. If your WG "hole" is to small the WGA will hold the puck open the whole time trying to lower boost. Boost will creep and spike both depending on the size of the turbo, RPM etc. So yes, too small of a WG hole will cause the WG puck to never close.

What are the two forces working the WG port?

You're telling me that I'm wrong and at the same time you're agreeing with what I had previously posted, quoted in bold below. We're not talking about high boost though because, if we were, boost creep wouldn't be the issue...

2 forces are exh. and int. pressure. I agreed with the point about the "blow open". Not the rest. A larger WG would solve the OP's creep issue as well. So would a larger turbo which makes more sense.

Once again, you're saying I'm incorrect yet agreeing with what I'm saying in your statement, see bolded quote below.

Exhaust will flow like water, taking the path of least resistance. If the path of least resistance is across the turbine (exhaust wheel of the turbo) the turbo will continue to build boost.​

Huh, I don't see anything above that I agreed with?

You imply that the exh. pressure will magically bypass the WG and flow directly into the turbo. That is not the case. Exh pressure is not bypassing the WG hole, the problem is the WG hole is not large enough. A larger WG would fix the creep issues, again so woudl a larger turbo.

Maybe I'm misunderstanding you correctly because board communication can be a bit tough at times.

Assume you're running an HX35 in the .55 A/R BEP housing and you've got two wastegates, one's a MV-S (38mm) and the other is a MV-R (44mm) both using the same 1BAR spring. From what you're telling us that by installing the bigger MV-R wastegate you'll waste more exhaust gas and the turbo won't spool as efficiently and power output will be less?

You are correct, the bigger turbine housing (A/R) and turbine wheel will definitely lower exhaust gas velocity across it and effectively lower backpressure while doing so but, again, what does the size of the wastegate have anything to do with power output? Nothing.


Again, you're disagreeing with me and then typing it up to say the same thing I just said.

Not the point I'm making at all. You are trying to tie separate topics together. Your example above is poor because either of those gates could properly control the turbo you mentioned. In the case of the 16g the original gate is to small. (see #3)

1) If a turbo is sized for peak efficiency it won't need a waste gate. It will be sized to the engine and rpm range it is being used for and will direct all of the exhaust energy into the turbo. This way no exh energy is being wasted.

2) Regardless of gate size, any exhaust not ran through the turbo is power wasted. Hence the term "wastegate"

3) WIth the OP's situation, the WG reacts directly to the power being made. How can you say it doesn't? Strap your e316g dsm to a dyno and remove the WG puck all together. As shown above the car will still make 20+psi. (say 280whp) Now weld the internal gate closed and install a 50mm external gate with the guts removed. How much boost will it make? You don't think it will result in less power at the wheels? How is the WG not related directly to power being made?

Your argument seems to be that if a turbo and WG are properly sized to start with would a larger gate result in less power. I'd say of course not. But that doesn't relate the the OP. Who is over running the 16g WG.

 

[Diamond Star Werks]

You imply that the exh. pressure will magically bypass the WG and flow directly into the turbo. That is not the case. Exh pressure is not bypassing the WG hole, the problem is the WG hole is not large enough. A larger WG would fix the creep issues, again so woudl a larger turbo.


Ok so tell me, if the wastegate hole is to small to evacuate enough exhaust where does it go? Over the turbine. What happens when more exhaust goes over the turbine? More boost.
He didn't say that all the exhaust bypasses it cause its too small just that if its too small more exhaust will flow over the turbine causing boost creep.

 

[forcefed86]

You imply that the exh. pressure will magically bypass the WG and flow directly into the turbo. That is not the case. Exh pressure is not bypassing the WG hole, the problem is the WG hole is not large enough. A larger WG would fix the creep issues, again so woudl a larger turbo.


Ok so tell me, if the wastegate hole is to small to evacuate enough exhaust where does it go? Over the turbine. What happens when more exhaust goes over the turbine? More boost.
He didn't say that all the exhaust bypasses it cause its too small just that if its too small more exhaust will flow over the turbine causing boost creep.

I never said it wouldn't. I said it wouldn't bypass the WG hole. You just restated what I've said 3 times now.

 

[Diamond Star Werks]

Also 20psi with an internal gate is.20psi with an external. Off course course you lose power with a, wastegate versus one without but without one you lose all reliability and run out of effiency and just, start blowing hot air into the engine.
turbos have wastegates for the same reason an engine has a rev limit abd gears. To keep it from over revving/spinning and to keep it in peak effiency. No matter what size size engine you can't match a turbo perfectly, its not a perfect world. Either the engine or turbo would need a limit. Or the turbo would eventually destroy itself.
Exhaust gas must be limited for the sake of the turbos life. To run a turbo without a wg and keep its reliabilty you'd have to limit the engines rpm to limit the exhaust expelled. Without exhaust limitation a turbo would never last.