These are gold, we could not make this up even if we tried. They shoiuld make a movie out of this...

Oh wait they did, starring Jennifer Lawrence summore

The main issue with VGT is heat, the additional components don't hold up well with heat.  VGT mainly used by diesel because the peak exhaust temperature is lower than petrol combustion, so heat issue on diesel engines is less of an issue. Also, VGT somehow has better advantages in inducing EGR for emissions reduction.

Still stuck with fairytale mentality? VGT design is far simpler than twinscroll. There's no such thing as VGT generating more heat.  Whatever heat and pressure come from exhaust valve, turbocharger is just mechanism powered by exhaust gas. Diesel engines favour VGT because of simpler less carbon buildup and easy cleaning compared to twinscroll turbo.

Walau eh, stated so clear already also Dr Jay can interpret as VGT generate heat. It means the VGT additional components tak boleh tahan panas bro, not VGT generate heat.

Your English fails or your logic fails?

VGT design far simpler than twinscroll, you must be kidding me.

Even if it's not twinscroll, the design of its exhaust manifold that make port 1 & 3 clash with 2 & 4 to generate strong pressure allowing the new low inertia impeller to draw enough dense air from lower rpm. The design of the engine, air intake curved angle count as well.

Erm, what is that? Your twinscroll understanding terbalik ke?
We don't want them to clash lah, and one of the  single scroll turbo workaround is the plenum chamber.
Wah, your favorite plenum, this is your stage! Come teach us what is plenum.

Twinscroll is to preven interfering among all the 4 cylinders lah.

Use general 1,3,4,2 firing sequence.

When 3 exhaust, 1 is at its intake stroke. The 1 exhaust valve would be still open at the beginning of the intake cycle to overlap with intake value for the scavenging affect. Exhaust pressure from 3 would interfere with 1. That's why twinscroll split to group 1,4 and group 2,3.

VGT mostly in diesel engine mainly because its design is more simple. Diesel engine has far more carbon buildup so it need s more simple straightforward approach to avoid high carbon buildup and difficulty in cleaning.

When popularity of stock cars with turbocharger came, there's already twinscroll turbocharger available. So they went for twinscroll turbo.

I have to disagree on VGT being more simple. If got chance, you try open up 1 and see. Twin scroll is far more simpler as the changes is the exhaust housing design which is easily can be removed and installed back compare to VGT.

And as what the others had shared VGT is very sensitive to heat, especially the vanes.
http://www.enginebuildermag.com/2014/07/te...-turbochargers/

Most petrol engine use twin scroll as it is a much simpler system and more reliable.

Hope this corrects some of your misunderstanding.

You have to remember, he keeps all knowledge in his mind. To him, what's the point of referencing from "infected" auto journalists when his mind is mind blowingly more "reliable"? He is the professor in this forum and possibly the most knowledgeable in malaysia conservatively speaking....

From your wastegate talk, you proven yourself to know shit about the fundamentals of air charging, don't even go down to the intricacies of individual components.

VGT design is not simpler than twinscroll, you forget got additional components to do the actuation to change the exhaust flow angles before the impeller?

And you don't even understand what i commented, i never mentioned VGT generating more heat. You don't understand  about heat effects on VGT, you just simply blurt out whatever you think is right.

As you like to simply simplify complicated things just for your understanding, instead of really understanding things the way it is.

Your talk about cleaning the turbocharger is just trash. You don't understand the construction of turbocharger. Both are complicated to clean in their respective manner and VGT should actually take more effort to clean as need to involve additional directional fins.

The only thing to complete in your sentence is full stop, hardly any verifiable facts in reality.

Ya i know, you don't need referencing because you remember things in your mind. Great infact. But you don't understand things in the first place, what you remembered and recall will just be plain falsehood. And when pointed out, you never go to verify and figure out, you just hold whatever your initially flawed understanding as sacred. With almost 40 years of accumulated experience, it still proves your understanding is simply FAIL....

Eh why so complicated....

By mr j's standards, twinscroll means 2 impellers; one for lower pressure exhaust to spin, the other when higher exhaust pressure available to spin.

What the heck were you trying to twist and turn? Want to confuse non technical people kah?   

I'm not surprised at all that you failed to complete the half details I posted on twinscroll turbo. So are the few of your buddies here except they backed off upon seeing the details. You're probably the weakest amongst them. Kesian, let me sedekah you the other part.

As told you, there are 2 inlet where 1 for low pressure and 1 for high pressure that goes into impeller. The exhaust manifold ports for 2 cylinder chambers that start first linked as low pressure manifold that goes into lower pressure inlet. The 2 more chambers exhaust linked into high pressure inlet. These 2 inlets called as twinscroll that flow low and high exhaust gas pressure to impeller allowing it to spin the compressor fast enough to effectively draw in dense air into combustion chamber. That's twinscroll turbo could assist from as low as 1200rpm in some configuration layout.

So you still want to talk fairytale?

@constant_weight replying to you too

My version

Dr J : Preve turbocharger is primitive!
me : Elantra Sport use turbocharger from same company
Dr J : NO!! Elantra Sport turbocharger is VGT, boost to 1.5 bar. Preve primitive turbo low boost and lag.
me : Elantra Sport stock turbocharger is twinscroll and boost only to 0.9 bar.
Dr J : People like to round up 0.9 to 1.0! Elantra Sport VGT that activate from 1500rpm is not primitive!
me (thinking): Hmm, praise my car woh, saying it is not primitive.
Dr J : Elantra Sport won't sell well, I can help them boost the sale but I won't help them since they hurt friends.

Yea if he says something good about Korean car, you know what's coming next.

You lost and started to reply to yourself.

Turbocharger primitive or advanced is judged based on type of turbocharger and the layout from intake to engine to exhaust.

The fiesta 1.0 ecoboost trying to minimize cost using 4-2-1 exhaust that spiraled to give it similar effects of twinscroll except its using single scroll turbo and able to assist from 1600rpm onwards. If it's fitted with twinscroll, it could assist from much lower rpm maybe 1200rpm onwards and reduce its underpowered no assist low end rpm.

Preve if it's using the same turbocharger as Fiesta, it could only assist from 2000rpm onwards, that's no different from Kenny's shop fitted turbocharger.

You know that 1.5 is taken from tweaked version Elantra sport. I really pity you and those Korean marketing staff, so eager to know how and what he did with that car.

You know the rules. When my buddies joined different companies, they won't be evaluating cars together anymore but with their own team. I wasn't there to evaluate and my point is to show the difference between new generation turbo and old generation obsolete turbo. Be it VGT or twinscroll, the conclusion is both are new generation turbo and able to put them to work only count as advanced.

Whereas modshop like Kenny and Preve turbo, these are examples of failures.

You have to remember, he keeps all knowledge in his mind. To him, what's the point of referencing from "infected" auto journalists when his mind is mind blowingly more "reliable"? He is the professor in this forum and possibly the most knowledgeable in malaysia conservatively speaking....

The fiesta 1.0 ecoboost trying to minimize cost using 4-2-1 exhaust that spiraled to give it similar effects of twinscroll except its using single scroll turbo and able to assist from 1600rpm onwards. If it's fitted with twinscroll, it could assist from much lower rpm maybe 1200rpm onwards and reduce its underpowered no assist low end rpm.

HAHAHAHAHAHAHAHAHAHA

k3nnykl82 Eh bro I ask you. Have you ever seen a 3 cylinder use a 4-2-1 manifold? The extra runner must be for decoration

Dr.Jay, not only you don't know that the 1.0 ecoboost is a 3 cylinder, you also don't know that it uses a 3-1 extractor that is built into the engine head. From outside the engine you can only see a single runner bolted to the cylinder head that directs the exhaust stream to the turbine housing.

As always, you don't know anything, but try to throw statements pulled out of thin air and try to pass them off as facts, hoping that nobody knows better. Unfortunately for you, everyone knows better than you.

So you still want to talk fairytale?
@constant_weight replying to you too

Even if it's not twinscroll, the design of its exhaust manifold that make port 1 & 3 clash with 2 & 4 to generate strong pressure allowing the new low inertia impeller to draw enough dense air from lower rpm. The design of the engine, air intake curved angle count as well.

The detailed facts version wastegate function explanation puts most of you quiet because it is correct and shamed few of you who actually didn't know wastegate valve complete functions.

The VGT actuator is not in the exhaust manifold side but only at the other end of the impeller. All it does is only extend or retract the blades or fins for high or low exhaust pressure operation. The VGT turbocharger cleaning mostly on exhaust manifold and impeller, cleaning is easier and less prone to carbon buildup. Your comments clearly tells that you've never seen how people clean up carbon buildup especially diesel engines. Lol, you sure think brushing only. You should check how complex the twinscroll exhaust turbocharger and its exhaust manifold first.

I'm not surprised at all that you failed to complete the half details I posted on twinscroll turbo. So are the few of your buddies here except they backed off upon seeing the details. You're probably the weakest amongst them. Kesian, let me sedekah you the other part.

As told you, there are 2 inlet where 1 for low pressure and 1 for high pressure that goes into impeller. The exhaust manifold ports for 2 cylinder chambers that start first linked as low pressure manifold that goes into lower pressure inlet. The 2 more chambers exhaust linked into high pressure inlet. These 2 inlets called as twinscroll that flow low and high exhaust gas pressure to impeller allowing it to spin the compressor fast enough to effectively draw in dense air into combustion chamber. That's twinscroll turbo could assist from as low as 1200rpm in some configuration layout.

So you still want to talk fairytale?

@constant_weight replying to you too

Ohhhhh
Twin scroll... One inlet for low pressure.. One for high pressure... Bagus sekali..

Infected journalist twist results like you. I still post facts except with restrictions by not posting pros of brands that challenge my buddies side. Nothing wrong with that. Korean cars lost, that's the Korean management fault. I'm just news commentator now.

Latest news, you can see how high Koreans throwing discount now. Starting to get cheaper than Japanese B segment cars and SUV. The principal blamed Malaysian taste, distributor blamed principal and sales blamed distributor. Why they never blamed themselves? They said economy not good but how come Honda CRV that priced 145k, 160k getting more and more on the road while cheaper new elantra and cerato still non on the road? Civic turbo also has more. Now city hybrid also can be seen on the road.

Inquiry done on several owners, they said they went for Honda because the Koreans look like they are going down, they never thought of buying even if price cut until B segment because it's still a big liability. You can see how effective my buddies strategies are.

...As for Honta, it is never reliable with much technical issues but people tend to keep 1 eye shut because of Honta brand. You don't have to argue, I encouraged everyone to find out the facts personally, rather than buying crap marketing rumors spread by you bunch of cheaters....

....Marketing job, the Japanese already done more than enough. Local Marketing crap that don't even know what is car, get all the credits. People buy the car because of having people to maintain and keep the car running. Not because of the sellman or the marketing staff.....

....due to best marketing by Japanese management, not the local crap management.....

......is its brand power and effective marketing from Japan.......

Damn the exhaust header design must be damn advanced and need additional wastegates then   
Oh wai.....