Turbine Housing Rb25 Gtx3076 Divided

[PatMol]

Hi Folks,

Project:

Manual conversion of S14 (that got out of hand)

SPEC

Motor: Stock RB25 NEO

Injectors: TBC 100cc

Pump: walbro 450

Turbo: Gtx3076R

Exhaust: 3" with unknown sports cat

Manifold: 6Boost Top Mount T3 Divided single gate

Power Goal:

Ideally 288kw to 300kw not fussy as I want to drive the car

Garret have a shortage of .86/AR exhaust housings which is what iv seen used on the build threads here and in the dyno section.

I ideally want a derivable daily car and I get it the turbo might be a bit big and prob should have looked at a gtx3071 on a stock bottom end NEO.

So here is the question. Will I get away with a divided .78Ar housing at 288- 300kw mark?

Should I order it and shut up?

Should I stick an open .63 on it and have a very expensive open manifold while i wait for a .86?

I Searched:

http://www.sau.com.au/forums/index.php?app=core&module=search&do=search&fromMainBar=1

Projects

AngryRB

http://www.sau.com.au/forums/topic/426934-angryrbs-r33-street-sweeper/?view=findpost&p=6906326&hl=%2Bgtx3076-- Went with another turbo in the end

DiscoPotatos Gt3076

http://www.sau.com.au/forums/topic/440226-gt3076r-antics-better-late-than-never/?view=findpost&p=7223471&hl=%2Bgtx3076

Sort of relevant:

http://www.240sxforums.com/forums/rb-tech/105515-550rwhp-rb25det-my-build-88.html

http://www.sau.com.au/forums/index.php?app=core&module=search&do=user_activity&mid=24715

[Dale FZ1]

You are probably looking at a Garrett vs ATP housing. There may be a difference in the quality of the casting. What is the difference in price?

To have any hope of the hotside keeping up flow wise with the GTX compressor, you'd probably want the bigger turbine A/R. I'd suggest the 0.78 might choke a little early. RB engines respond well to a decent flow capacity through the turbine.

Also, if you have reasonable access to E85, get onto that.

[PatMol]

I ordered the .78 if it chokes it chokes and Ill get a bigger housing if i need to.

its 850$ vs 300$

So when the .86 genuine Garrett comes back in stock it should be more reasonable.

I'm starting to feel like.

I

Edited November 19, 2015 by PatMol

[scotty nm35]

Even the .82 divided chokes the top end, I think a 1.06 would be better personally. If you want better response you should select a smaller turbo not choke a larger one imo. I have seen a GTX3076 run 400kw on e85 in Gregs auto 34 GTT recently, before his head lifted.

Here is a 0.82 split pulse twin gate 6boost setup I did a while back. The results are in the RB25 dyno thread under Owenliberts, I think he posted a few running 98 and e85.

http://www.sau.com.au/forums/topic/55845-rb25-turbo-upgrade-all-dyno-results/page-43

[PatMol]

Thank you scotty

Looks like I'll need a bigger housing.

Gives me room to add power then

[hypergear]

For 280~300rwkws, chasing maximum response, in Garrett range, I will be going for an GTX3071 in a single pulse .63 rear running an 44mm external gate.

[PatMol]

Thanks again guys for the suggestion. I really appreciate the feedback

I will see how we go and how far I am willing to push the stock motor.