Waste Gate On Standard Manifold Vs Waste Gate On Turbo

[Dose Pipe Sutututu]

Alright, I've figured it out. 3 gates -_-

I'm assuming 1 per side of the stock manifold and another gate off the turbo housing as well? haha

imagine the noise

[SkudR33]

that's horrible for flow, why not just weld a gate flange off the rear housing?

I can't figure out who to goto to get a wastegate welded on... I'd personally prefer it welded on the manifold.

[scotty nm35]

I can't figure out who to goto to get a wastegate welded on... I'd personally prefer it welded on the manifold.

Don't bother sending a manifold to me, I can't die grind the opening to the gate from the inside, and if I can't do a job properly, I won't do it at all. These 90 degree entry gate pipes welded in a hole... you are better off staying internal gate imo.

The housing on the other hand has great access. I can clean up the gate entry in no time.

[jay-rod]

Im looking forward to it

Turbo should be with Stao by now

[discopotato03]

Scotty do the GT Ni Resist housings weld ok ?

Also I was looking at Turbosmart 40 and 45mm external gates just to get an idea of their dimensions . What size external gates are being used on say typical RB25 GT30 setups in the 3-400 wheel wasp area .

I wish I could find the pic of a Turbosmart gate on the housing in a Skyline bay because it didn't stand out that much . I suppose real stealth would be having the gate closer to where the exhaust returns to the front pipe .

A .

[scotty nm35]

It is quite hard to hide the gate, as there is no room to weld the gate underneath the turbo. You could mount it down where the dump is, but the pipe leading to the gate will be a little longer than I would like. (Plus it would need to be welded onsite)

The GT cast iron housings are very hard to cut and diegrind, but they weld fine. Stao's housings cut like butter and take half the time.

I would use 45mm for the gate, or perhaps larger. The boost control would be fine with a 40mm, but power would be more restricted. The 45mm gates are the same size Vbands as the steampipe I use so they flow nicely.

[discopotato03]

Yeh I found grinding a radius into the GT IW T3 inlet port hard going . Cartridge rolls useless and ended up using a carbide burr and files .

A .

[r34unit]

from my testings, running the same turbo externally gated on turbine housing with stock manifold made less power then the same turbo on aftermarket manifold internally gated, and even lesser against aftermarket manifold externally gated.

Turbine housing has been untouched all times, the manifold is restrictive. So scientific solution would be attaching the external gate to the manifold. But factory manifold is twin log, do them properly requires extra work and skills, (I'm in process of building one at moment) while external gate from turbine housing makes the job easier.

Hay did end up building your manifold ?

Interested in what you came up with !

[r34unit]

Who modifies the center divider when welding the external waste gate port on the stock manifold !

Pics please and thank you

[scotty nm35]

You can't do much with it, or you will force the pulses into the other side of the log. The divider needs to stay. I would even extend it a little, to just before the gate.

I found better results by making the flow path smoother. You can't really do this running the gate off the manifold as you can't die grind it after welding.

[Ben C34]

Ok. Maybe I am spazzing out, but how late on the housing could the gate be welded on?

Now I know common sense says put it where everyone puts it, close to the inlet, but I don't want to!

I would like for ultimate stealth Ness to weld the gate pretty much at the end of the scroll, so it is directly under the turbo and hidden. (Using the stock manifold)

Is that too silly? The way I see it if the little internal gate flange can work pretty well, a less than ideal external gate would still work sort of good? I don't need to be able to run low boost

Whatcha reckon?

[GTSBoy]

I reckon the further around you put it the more restrictive the whole thing will become.

Remember 2 things. There is a total amount of exhaust gas that has to flow and there are 2 holes that it needs to flow out of. If the wastegate opening is early in the flow path (ie, on the manifold, or near the inlet end of the turbine housing) then that gas that goes out the wastegate does not have to flow around the steadily decreasing area of the scroll. If you locate the wastegate a fair way around the scroll, then all the turbine gas plus all the wastegate gas have to flow that far, instead of just the turbine gas. The back pressure will climb for every extra little bit further around you put the gate.

I wouldn't do it.

[Kinkstaah]

I think the issue with that (I asked Mr Scotty for the same thing) was that there's actually no room to put one there?

[Ben C34]

I think the issue with that (I asked Mr Scotty for the same thing) was that there's actually no room to put one there?

I could very well be dreaming, but I'm sure from underneath I can easily see the whole turbine housing. Maybe there's more room in a rwd stagea. Or maybe I am retarded.

[discopotato03]

The way I see it there isn't an ideal point to mount it on the manifold and the throat of the turbine housing is the largest area downstream of the six passages merging . Even then the mount angle sometimes isn't ideal but if you want part of the gas stream to change direction its easier to do that where the passage is larger .

For the work involved go the turbine housing or use an aftermarket manifold if you want the gate/s on it .

A .

[AngryRB]

Theres heaps of room underneath and it isn't much harder than having it higher up, mine was on a low mount 6 boost and still was enough room.

There was no boost control issue, it did seem a bit laggy though, but not sure if it was just the twin scroll ATP housing or not.

Edited August 5, 2014 by AngryRB

[Ben C34]

Theres heaps of room underneath and it isn't much harder than having it higher up, mine was on a low mount 6 boost and still was enough room.

20130508_123417 (640x480).jpg

There was no boost control issue, it did seem a bit laggy though, but not sure if it was just the twin scroll ATP housing or not.

Do you have a pic? The 6boost manifold positions the turbo different to stock doesn't it? Sort of like an hks cast one does?

[Ben C34]

No way!. You must have posted that pic in between me clicking quote or something.

Very sneaky.

[r34unit]

How much heat can an external gate take ? Will it matter if you mount one near a turbo housing ?

[iruvyouskyrine]

Ummm. You realise that the external gate has exhaust gasses flowing through it and is welded to either the exhaust manifold or the rear turbo housing? They withstand an incredible amount of heat. You can even get water cooled gates.