EvoIII 16G Install Questions

[mnetwork]

I've done all my base upgrades and all I have left is the turbo and the things that go with it. Going to buy this within two weeks probably. I have some very important questions before I do though...

I am going to be buying everything off of SBR so I had a question about the 2g install kit. I just want to make sure that I will not have to buy a LICP (using the stock intercooler for now) if I get the install kit.. Is this so?

I am doing things in stages so without putting in the afc will I be safe to run at 16psi with the new turbo until then? Would running at 16psi with the 16g be any different than running it with the t25?

How much do you recommend the "$100 Upgrade" shown here >> http://www.slowboyracing.com/more.php?id=93&??

Thank you in advance for the replies.

 

[skinnykenny84]

and I am going on my own personal experience and about 1,000 other people on this forum with the same problem

 

[skinnykenny84]

just do a search on this turbo and boost creep and tell me that all the results are a big lie and conspiracy

 

[spyderturbo007]

I'm going to say this one more time and then I'm done, because I feel like I'm trying to ice skate uphill when talking to you.

Boost creep is caused by running low boost. At the point of low boost, the wastegate passage is unable flow enough exhaust gas to bypass the turbine housing. When this is the case, an upgraded flapper is a great idea. It enlarges the passage and allows a higher flow of exhaust gas. The problem surfaces when you attemp to increase the boost. The higher pressure causes the wastegate to blow open because of the increased force applied to a larger surface area. When the wastegae blows open, the boost will drop off and you will not be able to maintain your set pressure.

The sure fire way to cure boost creep is to crank up the boost. That way the majority of the exhaust gas is flowing through the turbine as opposed to through the wastegate passage.

So, as you can clearly see, an larger flapper is great for low boost, but sucks for high boost.

You guys feel like if you fill this guys thread up with alot of big numbers and math that he dont even understand that that will help him.

Just because you might not understand "big numbers" and math, doesn't mean that he doesn't. What is wrong with providing proof for a statement? It's better than just spouting off some "you should get this" crap.

 

[skinnykenny84]

anyway you keep saying low boost and high boost on this turbo, why would you want to run HIGH boost on this turbo anyway?? If hes gonna do that maybe he invest in something a lil bigger. I guess it depends on what YOUr deff of high and low boost is on this particular turbo

 

[skinnykenny84]

I'm going to say this one more time and then I'm done, because I feel like I'm trying to ice skate uphill when talking to you.

Boost creep is caused by running low boost. At the point of low boost, the wastegate passage is unable flow enough exhaust gas to bypass the turbine housing. When this is the case, an upgraded flapper is a great idea. It enlarges the passage and allows a higher flow of exhaust gas. The problem surfaces when you attemp to increase the boost. The higher pressure causes the wastegate to blow open because of the increased force applied to a larger surface area. When the wastegae blows open, the boost will drop off and you will not be able to maintain your set pressure.

The sure fire way to cure boost creep is to crank up the boost. That way the majority of the exhaust gas is flowing through the turbine as opposed to through the wastegate passage.

So, as you can clearly see, an larger flapper is great for low boost, but sucks for high boost.




Just because you might not understand "big numbers" and math, doesn't mean that he doesn't. What is wrong with providing proof for a statement? It's better than just spouting off some "you should get this" crap.

Why do you keep putting words and ideas in my mouth. I dont know if hes gonna run high boost or low boost or not. Im talking about everyday driving on this turbo within its effecientcy range. witch is low boost. This turbo isnt even that effec on "high" boost. Why dont we ask the guy who originaly posted this thread how much power he wants to make and how much boost he wants to run daily before attack me about the low boost high boost shit???? And I agree totaly 100% on your wg upgrade theory on high boost applications. But I could of swore that the guys target for now is 300hp, to ME that isnt HIGH boost.

 

[skinnykenny84]

do you see where Im coming from??

 

[ShapeGSX]

Some people do get boost creep. Some people don't. There are so many variables that can affect this that it is impossible to predict if a certain setup will creep or not.

What I am saying is this:
1. Try the turbo without porting it first.
2. If you don't creep, great! You're done!
3. If you do creep, see if you can live with the level it creeps to.
4. If you can't live with the level it creeps to, it may be possible to reduce the creep by installing a set of aftermarket cams.
5. If you don't want to do that (I understand they are expensive), then take off the exhaust housing and port the inlet so that the wastegate can scoop the exhaust out of the stream.

Like this: http://www.dsmtuners.com/forums/showthread.php?t=186525

But I would not, under any circumstances, install a larger flapper valve. An Evo III 16G can't have its wastegate ported enough to make a larger flapper valve of any use. The larger flapper valve will get in the way of the exhaust since it only opens up about 1/4". The larger flapper valve will not seal at high RPMs because the force on the valve is proportional to the square of the radius of the valve. Therefore, your boost will fall at high RPMs. It is just a bad idea all around. I made the mistake once, I won't do it again.

The cams thing is just a theory of mine, since the guys I know who already have cams and install Evo III 16Gs do not have boost creep issues, and their turbos are not ported. It could be something else, though. And cams make your car faster. You will be able to run more boost and flow more air with the engine with the cams, and it could get rid of your creep, too. Everyone wants to go faster, right?

Sometimes you just have to think a little differently than the majority.

 

[skinnykenny84]

Now you say , "the sure fire way to cure boost creep is to crank up the boost." Now thats great advice for a noob that barely knows what a 16g is!

 

[skinnykenny84]

Some people do get boost creep. Some people don't. There are so many variables that can affect this that it is impossible to predict if a certain setup will creep or not.

What I am saying is this:
1. Try the turbo without porting it first.
2. If you don't creep, great! You're done!
3. If you do creep, see if you can live with the level it creeps to.
4. If you can't live with the level it creeps to, it may be possible to reduce the creep by installing a set of aftermarket cams.
5. If you don't want to do that (I understand they are expensive), then take off the exhaust housing and port the inlet so that the wastegate can scoop the exhaust out of the stream.

Like this: http://www.dsmtuners.com/forums/showthread.php?t=186525

But I would not, under any circumstances, install a larger flapper valve. An Evo III 16G can't have its wastegate ported enough to make a larger flapper valve of any use. The larger flapper valve will get in the way of the exhaust since it only opens up about 1/4". The larger flapper valve will not seal at high RPMs because the force on the valve is proportional to the square of the radius of the valve. Therefore, your boost will fall at high RPMs. It is just a bad idea all around. I made the mistake once, I won't do it again.

The cams thing is just a theory of mine, since the guys I know who already have cams and install Evo III 16Gs do not have boost creep issues, and their turbos are not ported. It could be something else, though. And cams make your car faster. You will be able to run more boost and flow more air with the engine with the cams, and it could get rid of your creep, too. Everyone wants to go faster, right?

Sometimes you just have to think a little differently than the majority.

exactly, the larger flapper wont open all the way so thats why you port around it

 

[skinnykenny84]

your still assuming hes gonna be running "HIGH" boost levels

 

[ShapeGSX]

exactly, the larger flapper wont open all the way so thats why you port around it

The flapper (31mm, 34mm, doesn't matter) won't open all the way because the wastegate actuator won't push it any farther! It isn't being blocked by anything in the exhaust housing.

The wastegate actuator has a very limited throw.

I've applied pressure to the wastegate actuator before with the turbo off the car and watched the wastegate open. It will NEVER open 90 degrees. The flapper will always be in the way. It is better to have the smaller stock flapper in there so the exhaust can flow around the flapper more easily.

 

[skinnykenny84]

How many have you seen? Im sure a bunch, but I have seen em where the flapper would hit in some areas and the surface around it was not uniform so to speak. Ive seen it on 2 mhi turbos and 1 gt. To be honest the best looking one Ive seen so far come from the guy on ebay that everyone loves to bash because his prices are reletively cheap. And after further digging I found that you 2 guys are the only ones that say do not port it or upgrade the flapper?? weird.

Anyway so how do you know hes running high boost on this turbo and why whould he? you keep dodging that question? Thats the overall determining factor right??

 

[skinnykenny84]

So would you consider this information wrong?http://www.dsmtuners.com/forums/showthread.php?t=183108&page=1&pp=25
or this....

http://dsmtuners.com/forums/showthread.php?t=186525

 

[skinnykenny84]

This guy was running over 20psi and that to me is "HIGH" boost on this turbo

 

[oldman]

ShapeGSX and I, are providing real world experience combined with mathematical and observed data. I see nothing better than that combination.

Like I have said to ShapeGSX in another thread, theories are great and I'm gald it worked for the both of you but it doesn't mean it will work for everyone in a real world situation.

1. Both of you are creeping to 18psi, 18psi is a minor case of boost creep, perhaps your free flow exhaust system really isn't as free flow as you think . Most EVO III creepers are reporting at least 20+psi, 26 psi is fairely common so what do you suggest that these people do besides an external wastegate if porting is a big no no. Even if porting is bad like you claimed, life is about compromises.

2. Just because the three top EVO III times are none ported doesn't mean you can't achieve the same with a properly ported one, it takes a specially bred, like you guys , to try and take an EVO III into 11's, most people who are in 11's does it with a larger and more efficient tubo so it's unfaire to claim that a ported EVOIII will not get into 11's.

3. To port or not to port. I think we can all agree that three piece porting has been around for a while and the accepted wisdom is that it's a power gainer (and I'm speaking from personal experience). Just like when I challenged the accepted wisdom of tapping the BOV line for your mbc, it was up to me to prove why it's the worst place to tap, it was not up to others to prove to me that it's the best place to tap. The only way to prove your theory is to put it to test, I would like to see back to back dyno runs on your car with and without a ported EVO III housing. I seriously doubt that you will see a significant loss if any, I'm actually expecting to see gains.

4. Flapper. I agree that a 34mm flapper is known to blow open at higher boost levels and it's not needed at all to combat boost creep but again keep in mind that most who are running 26psi+ are either doing it with another turbo or with an external wastegate.

Don't get me wrong guys, I have great respect for the both you and you're definitely some of the more knowlegeable members on the site so I don't want to take anything away from you. I do however think that both of you are some what hung up on your mission of taking a virgin EVOIII as far as you can that you're losing some perspective on the subject. Remember that most of these threads about EVO III boost creep involves someone, right or wrong, trying to run the turbo at stock or near stock fuel systems while creeping to 22+psi so your special case/personal experience really doesn't apply to most.

 

[skinnykenny84]

OLDMAN to the rescue! I wasnt gonna ask you to come in here, I figured it was a matter of time before you let it get out of hand.

But really hes right, you guys know way more about this stuff than me, but I think like oldman said, you fixated on one way and thats to make the most power out of this lil turbo. I dont think the original poster has the same plan, thats all I was trying to say.

 

[ShapeGSX]

Anyway so how do you know hes running high boost on this turbo and why whould he? you keep dodging that question? Thats the overall determining factor right??

Why do the work and pay for it if it isn't needed at all and will reduce performance?! Hell, the large flapper on my small 16G made my my boost fall from 19psi down to 16psi. It made the car feel like a slug on the top end.

Here is a picture of the wastegate of an Evo III 16G:

You must be logged in to view this image or video.

How on earth is that going to hit anything if it only can open 1/4 of an inch because the actuator won't push it any farther?

Also, note that there just isn't a lot of wastegate meat to port out on that turbo. The big 16Gs were different. They could be ported a ton in the wastegate, though I still wouldn't want to. Also, if you port the metal too thin, you risk it cracking. My small 16G exhaust housing cracked in several places due to porting, unfortunately.

Also, this is a factory turbocharger. Did Lancer Evolution III's have trouble with boost creep without putting in a larger flapper valve? I bet not.

 

[skinnykenny84]

yea but not all e316gs look like that one! !

 

[kenamond]

Wow.

The pressure on a 34mm flapper at 20psi boost is 28lbs. Anyone know the length of the flapper arm inside the housing and length of the lever on the outside of the housing? Someone could easily figure out what the tension on the actuator arm has to be to hold the flapper closed at any level of boost. Can you put a different solenoid on it that has a stiffer spring/higher preload?

If the WG is only opening the WG flapper a little bit, why not fix that problem? A shorter lever on the housing would be one way, though you'd need more preload in the solenoid to compensate for the decreased mechanical advantage.

Seems like there are simpler problems that could be fixed before "going to higher boost" (read "live with the creep") which may require a lot of additional mods ($$$) and result in a higher hp goal than he wants (more things will break sooner). That might not be an acceptable solution to this guy. I know I'd have a hard time convincing my wife that I should dump $3k more into my car all at once to jump straight to 400hp.

As far as porting the turbo, I think the 2g mani needs to be ported or you're restricting flow at the collector. If you widen the mani collector exit, you have to do the same in the turbine housing (duh), and the gradual reduction in area as you approach the scroll will give a nice smooth flow. I agree that you can make it too big, but the 2g mani is too small. The desired experimental results would be to read backpressure in the mani before/after the port, but I don't have that evidence nor do I know anyone who has.

If the guy is targetting 300hp and is going to use an evo3, he's probably not going to run high boost, and he should be concerned with creep as a result. I'm not saying that he will definitely have creep, and perhaps it is wise to find out before you port, but that also means you have to drop the turbo again which will put his car out of commission for longer than if he can port the turbo before he installs it.

EDIT: Okay, I'm stupid. The pressure in the turbine inlet will not be 20psi at 20psi boost. More like, what, 50? 80? Something higher. I guess the test to do is find out the preload on the actuator arm and work the problem back to the backpressure required to match that preload.

 

[ShapeGSX]

Both of you are creeping to 18psi, 18psi is a minor case of boost creep, perhaps your free flow exhaust system really isn't as free flow as you think

If you heard it, you would think otherwise.

t's unfaire to claim that a ported EVOIII will not get into 11's

Ahem, I never did say that a ported Evo III won't get into the 11s.

Don't get me wrong guys, I have great respect for the both you and you're definitely some of the more knowlegeable members on the site so I don't want to take anything away from you. I do however think that both of you are some what hung up on your mission of taking a virgin EVOIII as far as you can that you're losing some perspective on the subject. Remember that most of these threads about EVO III boost creep involves someone, right or wrong, trying to run the turbo at stock or near stock fuel systems while creeping to 22+psi so your special case/personal experience really doesn't apply to most.

Note that I also try to steer people away from running this >40lb/min turbo on a system designed for half that airflow.

As far as I am concerned, you should always make sure that you have enough fuel flow capability to match the maximum airflow that a turbo can put out. Stuff happens, particularly on a newbie's car. You want to make sure that you have enough fuel to match any amount of air that your turbo can put out in case something goes wrong. Sure, it won't save your engine in every case, but it will at least give it a fighting chance.

Kenny, note what oldman just said (you know, since he has more green dots than I do ):

Flapper. I agree that a 34mm flapper is known to blow open at higher boost levels and it's not needed at all to combat boost creep

 

[oldman]

Also, this is a factory turbocharger. Did Lancer Evolution III's have trouble with boost creep without putting in a larger flapper valve? I bet not.

Again, it's unfair to compare two different cars especially of completely different setup. Did Lancer EVO III comes with a stock fuel system that is meant to support only 16psi? Did it comes with a stock exhaust system that is comparable to our upgraded 3" exhaust without cat? I don't think so. I'm sure this turbo will most likely not creep with a DSM stock exhaust system either.

edit: need to stop taking calls while posting.

 

[skinnykenny84]

Like I said, AGAIN, your right BUT, is he gonna be running "HIGH" boost on the turbo? If not then he would benefit from the porting. I just think we should clear this up before I get flammed and tried to be made to look like a fool.

 

[ShapeGSX]

Wow.

The pressure on a 34mm flapper at 20psi boost is 28lbs.

No, it will be higher. Exhaust manifold pressure can be as high as 2x boost pressure.

I never got around to measuring mine, though.

Anyone know the length of the flapper arm inside the housing and length of the lever on the outside of the housing?

Yes, I did. They are roughly equal.

Someone could easily figure out what the tension on the actuator arm has to be to hold the flapper closed at any level of boost.

Been there, done that.

31mm = 1.22"
r = .610"

A=3.14 * .610^2
A = 1.17"^2

34mm = 1.34"
r = 0.670"

A = 3.14 * 0.670^2
A = 1.41"

So, for 40psi of exhaust pressure (2x boost pressure):
Force(31mm) = 46.4lb
Force(34mm) = 56.4lb

That means that you have 21% more force on the wastegate actuator rod with the 34mm flapper than with the stock 31mm flapper.

Can you put a different solenoid on it that has a stiffer spring/higher preload?

Better bet is to find a 2 port wastegate actuator so the boost pressure tries to hold the gate shut.

If the WG is only opening the WG flapper a little bit, why not fix that problem? A shorter lever on the housing would be one way, though you'd need more preload in the solenoid to compensate for the decreased mechanical advantage.

As you imply, you don't get something for nothing. A longer lever would mean less mechanical advantage to keep that 46lb from prying your wastegate open.

As far as porting the turbo, I think the 2g mani needs to be ported or you're restricting flow at the collector.

Use the Evo III manifold instead and you get a perfect match. I don't think it needs to be larger than that. At most you might have two exhaust pulses going through the collector at once (probably one, but they aren't exactly equal length). There is more than enough room for them to fit through the collector of an Evo III manifold.

And if you use the Evo III manifold, you get to use the cool sealing ring to stop exhaust leaks at that gasket.

 

[2gGSX]

If you look at the above posts it's basically 1. the high powered Evo III users arguing to avoid doing things to the (well designed) turbo in order to not sacrifice the eventual goal of flowing ludicrous amounts of air and 2. people who want to run low boost levels on stock or near stock fuel systems and want to avoid boost creep.

Threads like these are exactly the reason why when someone tells me they have a stock fuel system and can't afford to upgrade within a relatively short period of time yet want an Evo III to boost to 14 psi I tell them to consider a T28 instead. If the people buying these turbos want nothing more than a quick street car with around 300 whp then I don't see why people do not look for other options instead of this new Evo III fad.

When's the last time you saw a thread about a Big T28 user complaining their turbo won't stay at 14 pounds of boost? Never.

Granted you CAN port the hell out of whatever you want or upgrade to larger flapper doors, but as oldman said,

life is about compromises.

Do this and you may no longer be able to hold high levels of boost (defined as in the general vicinity above 20 psi). If so, how much air are you flowing at this point? Not 40 lbs/min. If your goal is not to make ludicrous numbers and run 11's on a small turbo, then it may be time for people to be looking at other solutions. After all, the biggest advantage of the Evo III when compared to the Big T28 is that it is capable of flowing much higher numbers. If you take kill off that potential, what's the difference then?

 

[ShapeGSX]

Again, it's unfair to compare two different cars especially of completely different setup. Did Lancer EVO III comes with a stock fuel system that is meant to support only 16psi? Did it comes with a stock exhaust system that is comparable to our upgraded 3" exhaust without cat? I don't think so. I'm sure this turbo will most likely not creep with a DSM stock exhaust system either.

All I'm trying to say is that it is possible to end up with the best of both worlds so you can run both high and low boost with the Evo III 16G. It has been done on my car, several other DSMs, and even some Lancer Evolution III's.

You don't have to put on a larger flapper to combat creep (you agree with me, here). You can use the smaller flapper valve and still run low boost.

If need be, you can port the inlet of the exhaust housing to direct exhaust at the wastegate. Though that may also increase force at the flapper valve slightly, it isn't nearly as bad as the 21% increase in force that you get from the larger valve.

The point is to simply try the stock turbo out first. It may just work.

Larger flappers suck. Just say no!