Mjalaly

Yeah so the new turbo i am using looks like it uses a larger and different turbine housing (new version) than my old one. It has a different bolt spacing and a 3" outlet. So i would need to weld on a new flange to my resonator which is 2.5" with a reducer. The biggest issue is, that as far as i can tell, that this will shift everything quite a bit and my exhaust and waste gate will no longer meet up. I also cannot weld stainless! I can't find much info so does the GTX2867 and the GTX3076 use the same design? I don't want to commit to changing a bunch of the exhaust system if they are different (in case I don't like this turbo and go to the GTX2867).

TheShodan

iTrader: (14)

What you are comparing is a T31 2.5" 4 bolt to a GT 3" 4 bolt turbine housing. The volute of the two turbine housings are very similar, but the conical discharge of the GT series 4 bolt turbine housing pushes things out quite a bit more both physically and thermodynamically. The purpose of this is to really get the use out of the larger GT series turbine wheel profile, which doesn't even get happy until over 20lbs/min turbine gas flow (for a B16 a bit over 15psi or so).

In addition, the GTX2867R and GTX3076R are worlds apart in the way of responsiveness and size of both housings. Unless you're referring to what you have the GTX3067R., in which case, the compressor cover, compressor wheel, and CHRA length are the same. The difference being the turbine wheel and shaft. (The GTX2867R usese a 54mm exhaust wheel while the GTX3067R uses the same exhaust wheel and turbine shaft, heat shield and profile as all of the GT3076R family (Including the GTX3076R, GTX3071R,,GT3040R, GT3071R-2, and a few of its variants) which uses a 60mm exhaust wheel profile.

Now, the GTX3067R and GTX3076R do have an option for the T31 2.5" 4 bolt, but it's not a standard. You have to specifically request it when you order. Just going by " 4-bolt", unfortunately puts you into a different class of turbine housing. So, the housing itself isn't new at all, it was just that with the GT series, there are a ton of other options you have to be aware of.

The 60mm turbine wheel profile allows anyone to use the GT 3" 4 bolt turbine housing with it's wider bolt profile, but they aren't used on the smaller 54mm Turbines of the GTX2867R.
So, no, they don't use the same design at all. You start making changes and you don't like it, be prepared to cut, reweld, and replace flanging systems again back to what you had.
But, you can solve that by purchasing a GT(X)3076R Turbine housing that is a T31 2.5" 4 bolt configuration. That will at least fit your current downpipe flanging system from the GT3251B setup. Luckily you can buy the GT(X)3076R T31 2.5" 4 bolt turbine housings separately.

No matter how you slice it, going from a GT3251B to a GTX3076R is huge change in powerband to the upper rpm range on a B16 regardless of turbine housing style in the same A/R.. Get ready to really throw some boost at it. (Yes, even if it is a Ball-bearing CHRA).

Hope that helps a bit.

Mjalaly

That does make a ton of sense and does help. Pretty much this summed it up. So regardless, I cannot buy a GT 3.0" 4bolt for a GTX2867 correct?

The spacing from the center housing to the edge of the 4 bolt flange is going to cause the biggest problem, which will push everything out from where it is now.

TheShodan

iTrader: (14)

That is correct, sir.