I plan on using a least 4 different turbos (Wife allowing,lol) The one that is currently on there is a GT3076R with a .63 a/r Tial SS housing that has been cut up and refabricated to work with the stock turbomanifold and a Tial 38mm external gate. I also have welded a flange to the compressor housing to allow the stock elbow to bolt back on. The heat shield fits as well and hides the inverted gate.
I chose this as the starter for to 500hp and up crowd, as it's a proven performer on 2.0's for street/strip. I have faith that this turbo is going to shock even me with it's boost threshold in this app.
The GT35R is "outline interchangable" that is physically bolts in the place of the externally gated GT30's. But it too will require a reworked TialSS housing to bolt on to the ecotec turbomanifold.
The 35R has put 2.0's into the 10's and with more than 600hp on tap you'll be thinkin of forged pistons and Darton kit when you get to the limit of this turbo. But mind you it's just as happy making 300, so dont think a bigger turbo isnt going to have great low boost performance as well.
Rounding out my insanity I'll tig a 16ga 321stainless tri-Y and stick a GT4094R on there. That one I wanna try in two configs
- Tial SS housing in small A/R
-Garrett split tangential and Im going to shut half of it (the exhaust housing) off with a Tial 44 set @8psi with a master Tial set @22psi. I've done this before on a rearmount and it's functional for at least 3-400rpm off the boost threshold.
Going back the other way I plan on putting a internallygated Gt3071R with a 2.75" inlet.
It appears that the top 2 studs of the KO4 flange arn't that far off T-28. There is a strong possibility of an single plate adapter solution, but I make no promises until I put it together. That would garuntee the stock DP would work. at least from a concentric point of view.
If I can pull the singleplate adapters off, any t-28 flanged turbo can be used.
The internally gated turbos will have a Bosch bypass valve built into the compressor housing and the flange welded to the compressor for the stock elbow as well. I want the internally gated turbo's to be a turbo only swap. No maf swapping,exhaust changin' none of that.
These biggest of the T-28 flanged turbo's, the GT3071R-WG,will max out @475hp and will make a low 12 second car, other hardware permitting.
As far as the intake manifold goes there are plenty out there, you'll just have to either plug the fuel rail or use them for alky injection (megasquirtanyone?)
But Ive got a hankerin' to try a dissolving buck (no not $$ but Ironically that too) mold.
Thus far to make 3D parts,we have used the CNC to make 2 piece molds from MDF and either lay them up in 2 pieces or roll the carbon around the inside and blow a bag up inside it. It's very time consuming.
A dissolving buck mold uses either styro (messy) or plaster to do your layup over the top of. Then vacuumbag,postcure and use either MEK,Acetone (for styro) or plain old water for plaster (prefered,more greeen friendly
)
The results,if done correctly can be stunning. Superior runner dimentions, finish and a 7lb manifold that can take 50psi and 400deg. (it's all in the epoxy used)
like this one i found on the web
Thats the kind of manifold I tentivly have cookin on the back burner. I beleive it will have the 1000hp garret WIC core inside the plenum. It's very effective at resolving cyl/cyl issues @ high flow rates.
One thing I'd like to add for eveyone to consider. ALL of these turbos, even the 800hp GT4094 is within the realm of the factory PCM.
It's opsystem recognizes up to 912g/sec stock! For those of us that have had FI gm cars before and werent aware of that fact go ahead and do a
around the laptop.
Everyone else: that means the MAF wont "maxout" and cause a code when the mods get crazy, and the PCM is capable of understanding and properly fueling the 80lbs/min are going thru the motor.
Now with that statement goes this disclaimer - It needs to be fully unlocked by HPT to take it to the limit and I am, so far, unaware of the true limitations of the stock fuel system. I bet the Gt30 or 35 is going to reveal what that is.
I do know that step 1 to solve it will require a MSD BAP..
Linear Mode
