Hi guys!!! Some friends of mine have been doing this modification to their evos, I told her that this change is not quite correct since due to the evo have twin scroll turbo and with this mod they are only releasing two-cylinder pressure. The comic is that it has been successful, they have good control of boost pressure.

My question is, may have some implications with this rare modification?


This is a picture of the modification they make:

 

The image is a montage is just to illustrate the modification that they make.

 

I would love twin mvs on my stock manifold. Some ni rod and a little love.

 

Post one pic to see the job

 

So, what turbo is your friend using along with this setup? Also, what is the reason for doing this WG mod in the first place? I prefer Ratty's suggestion of plumbing in a second remote gate.

 

Some guys with the stock turbo another friend with the Evo 9 stock turbo, they like the sound produced by dump of the external wastegate, the internal wastegate is always closed, they are controlling the boost only with the external wastegate.

I said that this is not a good modification, but they keep making this modificación that has worked well for them.

 

If it works it works but like you said and if I am correct it is only releasing pressure from 2 cylinders. Don't know how it works at all.

 

Two cylinders is more than enough.. just because its asymmetric does not mean its no good. Is it the best? Idk, Idc !

 

Then we can conclude that there are no implications in this modification and is a good way to have external wastegate without much modification.

My friends do not even removed the exhaust manifold, only made a hole, welded one flange and put the wastegate, is a job of one or two hours max.

 

I would remove, because cast shavings and to properly weld to cast requires a specific process. But to each is their own. I'm sure it also slightly effects ve of that bank one way or another even if so minuscule

 

My friend that have your evo 5 with this mod, Evo 8 ECU and the evo 9 turbo is going the dyno to tune your car on Saturday of next week. I will post the results.

 

If you drill the hole while the car is running, you should keep the shavings out of the turbo.

It is pretty ghetto the way you are describing and they are only doing it for sound. Easier to add a externally dumped turbo outlet.

 

Also they like the look to have the wastegate on the top of the exhaust manifold.
To me what you say is harder to do, you must remove the turbo to do a externally dump tube in the turbo outlet and this job going to look ugly.

honestly I had not done any of the two jobs.

 

DSM guys have done this mod for years. But you also have to remember 1g/2g mannys are not devided. weld the stock flapped up and your ready for solid boost control for the most part.

 

I am curious as to how they have gone about keeping the internal gate always closed. Did they weld the flapper valve to its seat on the turbine housing? Did they hook a chain or cable onto the flapper valve's pivot arm to keep it shut? Or did they wire the flapper valve shut? Just wondering?