Here is a side view of my exhaust.... So I've been wrecking my brain trying to figure out why this thing wont run worth a E36 M3 over 10 psi... While scouring the net trying to figure out what this turbo is, I ran across something that really caught my eye...
That's my downpipe... on a smaller turbo than stock My GT2871R is considerably larger that the stock VJ-11.
Stock( 2.2Liter F2T) VJ-11 on the Left, Stock(1.6Liter B6T) VJ-14 On Right
Oh god. That E36 M3 is too small for a b6, let alone an f2.
You're going to E36 M3 if you get that setup from David.
Gonna sell that GT2871R, he recommended to post it to a SR20 fanboy site. should be worth more than enough to cover a new T3 ;-)
Well, that discharge housing is definitely a POS and replacing it will get you a ton of power potential..
AFTER you fix the real issue it's having. 
The whole losing all power thing is not exhaust related. If the pressure on the backside of the turbine built up because of exhaust restrictions, the turbo would lose the ability to make boost. Only AFTER it went to 0 psi in the intake would the engine lose the ability to accelerate the car.
Also, there's nothing in the t3 family that will flow more on the compressor side than a gt2871R. You'll end up with a t3/t4 hybrid if you want to have the same power potential from the compressor side. What would it cost you to get a better turbine housing for the 2871?
Guy by the name of "N2o_Matt" on mx6.com was running one of those Holset VGTs on one of these motors a couple years back. In testing, he found he could get the car to die completely if the turbo was necked down and he tried to rev it. Opening it up gave no issues.
My guess is that's what we're seeing here.
The problem with getting a better turbine housing for his 2871 is that it's not REALLY a 2871 at this point. Only the compressor side is T3-related.
I can only imagine what your EGTs look like. 
I'm guessing that's how you managed to turn your cast iron manifold BLUE.
In reply to Swank Force One: "I can only imagine what your EGTs look like. I'm guessing that's how you managed to turn your cast iron manifold BLUE." David told me the same thing.
In testing, he found he could get the car to die completely if the turbo was necked down and he tried to rev it.
Was it making 15psi of boost when it died? I'm 99.99% certain it wasn't. The boost gauge in those videos is why i think the turbine discharge is not "choking" the engine down to 10hp @15psi and 4500 rpm.
But now that im thinking about it, the terrible turbine discharge could be causing valve float!
Im going to feel bad if i'm right, because then the problem would be the same part i said WASNT the problem, just for an entirely different reason.
Backpressure in FRONT of the turbo could maybe cause this by holding the exhaust valves open and causing valve float. Pressure in the exhaust port pushes against the back of the valve and if you have enough pressure pushing on the back, it will not seat. Pressure in the exhaust tract is connected to boost since it takes more exhaust pressure to make more boost. So the backpressure might not be too bad at 10psi boost, but when you try to go to 15psi and it has to make more pressure in front of the turbo to get that boost, that higher pressure keeps the exhaust valve from seating, which causes valve float.. which means almost no power, and unburned charge gets pumped out the open exhaust valve and burns in the exhaust, which would cause high EGTs and possibly the coughing/blips.
And the turbine discharge COULD cause higher pressure in FRONT of the turbo because the turbo operates off a pressure differential and any increase in pressure on the exhaust side requires a proportional increase in pressure on the inlet side to do the same amount of work. So, if there is 2 psi of pressure in that turbine discharge housing and 10 psi in front of the turbo, and you up the pressure in the discharge area to 3psi, you'd have to have 15 psi in the inlet to do the same work, now.
So there is my SECOND theory. The turbine discharge is making the drive pressure skyrocket, and it's holding the exhaust valves open. Should be able to verify this by partially or completely unbolting the discharge housing and driving it. If the bolts are long enough i would just turn them most of the way out so the discharge thing is sitting up off the turbo by like a 1/4". That should be enough to tell if it's helping.
What are you talking about? These motors don't suffer from valve float. Do you even know what that sounds like? Do you even float valves, bro?
Sincerely,
Probetalk, PerformanceProbe, and MX6.com
Id compare F2T valvesprings to mattress springs....no really !
Bro, do you even float? Hahahaha
So Dan, did you try it?
T3 flanged manifold arrives this evening.
Why B2000s got dual valve springs while the turbo 626s did not is one of the mysteries of the universe.
Now that the holiday is over... let the build of this beast continue. t3/t04e can be purchased and GT2871r sold.
Modified B-Series Downpipe
T3 Compressor 2871R vs T3/T04E
Getting her back together. Need to figure out Oil Lines and get it ready to retune, and behold the best running this car has ever experienced...
The Chernobyl Child is almost ready to fire up.... New and Much Improved.
I hacked up a B-series Honda downpipe to modify.
Vacuum Delete
I can't freakin wait to see this thing finally run at its potential.
Im vaguely sad that you're not directly testing my theory. Granted, even if you upgraded the valvesprings you'd still have wanted to ditch that ridiculous turbine/discharge housing, so i sort of understand. Still sad.
I'd have to swap turbos and manifolds again. I sold the GT2871R to free up some budget money...
http://s79.photobucket.com/user/dansXR2/media/VID_20140421_191552_204_zpsznj2shqz.mp4.html No downpipe or o2 sensor on, but it is alive once again.. This car refuses to die!!!
Its mobile again. The t3/t4 turbo pulls so hard on this thing, no more cutting out over 10 psi and 4500rpm rev limit... Now for paint prep. More pics to come
NICE! When I get my MX6 on the road we need to meet up. You ever drive up here to the 'Burgh?
On occation, Morgantown is close to 1/2 way from the Pittsburg from here.
Decided it wanted to go for a drive...
Nice plate!!
Fueling will be up to snuff, 750cc injectors are enroute. The thing is running really well @ 13psi, but I'm about out of injector with the 460's on a 255/lph Walbro.
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