New Garrett Gtx2860R / 2863R / 2867R

[The Mafia]

We really need to get this back on track. THis is NOT a single vs twin discussion.

Technology is getting better in both areas.

If I had the money I would be using one of those electric assisted turbos that the F1 cars use.

(and just to piss old mate "single is better" off, I would run twin electric assisted lol)

Edited July 22, 2015 by The Mafia

[jangles]

Will gtx2860 fit in -7compressor covers without the sleeve? Rears are smaller than -5,-10s, how about the front?

[mr skidz]

Will gtx2860 fit in -7compressor covers without the sleeve? Rears are smaller than -5,-10s, how about the front?

sleeve required for .60 comp covers but not for oem .42 as inducer is smaller on gtx2860. I believe it's because it was designed for response on restricted intake race cars the inducer had to be of the smaller diameter

[The Mafia]

Would the smaller stock compressor cover have any issues / restrictions at all if fitted and ground out correctly?

[mr skidz]

Would the smaller stock compressor cover have any issues / restrictions at all if fitted and ground out correctly?

Well it's all just guess work at this stage as nobody had documented results anywhere as yet.

but I'm leaning now more towards this setup over gtx2863

(I change my mind a lot)

they would both work just slightly different, remember the difference is supposed to be only 30hp per turbo in the proper off the shelf housings.

but we're not asking 400hp or 430hp from them either so don't worry too much.

only thing I see being an issue:

is "possibly" additional heat from smaller .42 housing from big psi like 30 psi plus which it may not get to? but considering how much more efficient that wheel is, it could well be more efficient than a -5 boosted to 2bar + in its .60 cover?

so maybe we can spare some efficiency here especially since I'm going E85 the natural cooling effect of this suites this type of setup.

now the benefits of the oem .42 cover:

it's gonna have response straight off the bottom like say -5 wheel in a . 42,

it won't outflow the turbine so no surge either basically same as a -5 but a comp wheel that shoots it's load into your pipework faster thanks to the .42 it even has the smaller inducer to suite the oem shitty intake snouts.

something to think about anyway.

[STATUS]

I don't care if twins or singles or semantics of the debate as there are loads of variables.... But one very good point is I would love to see the singles performance with the gate plumbed back so it's at least attempting to be a street able road car.

My experience, albeit at ~300rwkws and 80mm exhaust is it makes a huge difference to power, response and ignition the tune can take when switching external gate to plumb back...as an observation the quality of the front pipes seem to have a decent impact on twins too.

That said...if there was a reasonable process to getting a single thru roadworthy i would stick with a single every time....just for convenience and simplicity when banging around on track

yup, had the pleasure of tuning a twin -7 or -9's (cant remember which) on a ex-gated manifold and the difference was appreciable.

[gmchaser]

Why not just stick with -5. I have them running up to 1.9 bar in my gtr good power from around 4500rpm all the way to 8000rpm. That's a good useable powerband.

If it's a 3ltr that revs to 8000rpm I can understand as the -5 would probably be out of Their efficiency at that boost.

Edited July 22, 2015 by gmchaser

[gmchaser]

Oh and I also have just put a t04z .82 on a standard rb25 s2 and its a good 500rpm laggier than the -5 in rb26.

Both turbos set up flow up to around 70lbs/min

The t04z would be amazing in an rb26 with 270ish cams revving to 8500-9000rpm at 2.0bar.

I would think it would easier to get that set up running properly over twin gtx turbos.

Cheaper too

Edited July 22, 2015 by gmchaser

[Roy]

yup, had the pleasure of tuning a twin -7 or -9's (cant remember which) on a ex-gated manifold and the difference was appreciable.

Lol, yeh...i really want to run GTX2860s with Tial 0.63 A/R turbine housings with the T04B style comp cover with 3" inet and 2" outlets, all high mounted with twin Tial 8mm MVS gates.

Would be schmick setup but defeats the purpose of me going from the single as i need to go to a std looking setup on a std 26 to keep enjoying my car on the street. Nobody cares about my race seats, half cage, brakes...all they care about is under the bonnet

[Piggaz]

Trent, do you think the gain would be because you're relieving some of the gas from the already turbine housings?

I know Matt Femino made his own exhaust manifolds for the twins and found it "felt" a lot better despite the dyno reading exactly the same. IIRC.

They were not externally gated though.

[The Mafia]

I have fully ported exhaust manifolds, rear housings, and wastegate ports. The wastegate ports were cleaned up as much as possible without taking too much out.

Everything was port matched so I am hoping that is helping. Manifolds, rear housings and dumps all Cerakote coated too (1200 degrees).

Just need 2 x GTX2860 cores and my factory front covers bored to match.

[sneakey pete]

I didn't think you could machine stock compressors as the exducer is 60.1 instead of the 60.0 required for the gtx wheel?

[mr skidz]

I have fully ported exhaust manifolds, rear housings, and wastegate ports. The wastegate ports were cleaned up as much as possible without taking too much out.

Everything was port matched so I am hoping that is helping. Manifolds, rear housings and dumps all Cerakote coated too (1200 degrees).

Just need 2 x GTX2860 cores and my factory front covers bored to match.

how did you go, did you get it all done?

[sneakey pete]

If you did, did you run into any issues with the factory front covers on the GTX wheel?
That's the route i'm heading down at the moment, but any experiences people have had with that combo would be interesting

[The Mafia]

I haven't even moved with this yet. Funds and time is the issue.

Still tuning my -5s anyway. Managed to get them to come on pretty early, next step is closing up the LSA to see if it is any better.

[mr skidz]

I'd do it now if someone wanted to donate there old -5 rear housings to me lol..

where is the best place to buy JUST the -5 rear ex housing?

who's cheapest?

Edited August 24, 2015 by mr skidz

[Piggaz]

Ring GCG. $300 a housing or so I think.

[mr skidz]

spoke to them already and they told me that they don't sell those particular rear housings separately. So I ask them "so what you do is just import the whole dash 5 from overseas as a complete unit and sell it at a profit" and they said yes, they do not make them here.

I get nowhere with those guys

[sneakey pete]

MTQ has them for that price also, but, apparently Garrett have none in stock and aren't doing a production run until November.
Ended up that buying someones turbo's was the best option, so now i've got cores+rear housings, and a set of factory front housings that I will get machined to fit the GTX2860's into.

At this rate I may have the turbos done by mid September, But I probably won't install them until the new year. Would like to do them sooner, but i'd also like to have a working car for my 3 week roadtrip to Victoria

[Leroy Peterson]

guess daz is moving on from the GTX's...

http://www.sau.com.au/forums/topic/459552-2-x-gtx2867r-like-new/