Garrett Medium Frame Gtx Turbos

[GravyGarage]

Someone previously posted on here (I think it was Ozz) on an SR20 they were virtually identical - you'd be forgiven thinking they were the same turbo on different dyno runs.

Found it on another forum - scroll down to post 37.

http://www.silviawa....pic=58974&st=20

Hmm interesting. Have to pay an extra $440 to make the same result...

I cant see any reason to buy a gtx when you can get the bigger model gt turbo for a smaller cost. Is there something im missing??

[GTScotT]

For those interested, I found a GTX3076 result on toymods forum. The result was again a very lazy looking 3076... Power building very progressively and making SFA around the 4k mark, with a final result of around 300rwkw from a VVTI 1JZ.

Seen better results of .63 35Rs to be honest.. On non VVTI motors. Not keen.

[scotty nm35]

VVTI 1j's have very small ports though, I was surprised when I compared them to the VQ's.

I was planning to go for the gtx3076 but looking at the flow island it wasnt any wider than the GT3076, much higher though so the wheel should be much more efficient at high boost. Instead I went the GTX3071 as the efficiency should be much better for more of the rev range. Thats my theory anyway.

I should have it tuned next week hopefully, I have plenty of work to do before then though.

[joeyjoejoejuniorshabadoo]

so what is the point of the GTX then?

is it jut a big fail on garret's behalf? or is there actually an application where they are superior to the GT range?

[FineLine]

Why change what isnt broken Joey. Garrett have built a succesful business on failed products.

Simply find a way to deny 99.9999999% of warranty claims and sell the customer a new product every time the old one shits itself.

[juggernaut1]

so what is the point of the GTX then?

is it jut a big fail on garret's behalf? or is there actually an application where they are superior to the GT range?

Possibly where running race fuels (or E85) and a gut full of boost.

But for the average enthusiest using pump fuel, the selection of the correct GT series turbo for the application will likely net a better overall power curve.

Edited June 20, 2011 by juggernaut1

[Lithium]

Basically nothing I can see. ForcedPerforce have a range of turbos which are imho better answers to the existing Garrett range.

[ARTZ]

well it is Garrett so i very much doubt its a fail, could be some time before its win is found though through different setups and tuning.

i was reading some old threads finding info on my old tech to4s turbo and many were actually skeptical when the GT series of turbos first came out and thought the old tech was bettter. I mean even gcg thought they could relable a to4s and badge it a 3071r like nobody would notice a difference, no doubt they made some money doing this but they were obviously not as good and the line was dropped..Now the GT is probably considered the benchmar of modern turbos, so just wait and see I think there will no doubt be surprises in store

[rondofj]

Sorry to hijack; just dont get this -again a MONSTER torque figure close to 1300Nm, yet I see many skylines with very similar mods making in the 500-600Nm range in the RB25 dyno thread???? Mine made 545Nm and 186rwkw on stock turbo 12psi with supporting mods and I was doubtful of the torque figure as I think it was too high... people with twice as much power have made barely more torque than that, yet there are other people with huge torque figure in the 800-1000Nm range.. anyone care to pour a bit of light on this?

There we go.

[hypergear]

I think the design of those comp wheels are not really perfect for response. The blades are too tall and too straight, means there will be lot more surface area catching greater amount of counter forced under boost, requires more turbine flow to turn, result in lag. But possibly more flow per rotation resulting more power with less boost.

There is nothing wrong with the GT turbine wheels, and it is possible to generate more power and better response using more appropriate comp wheel design.

Having said that the GTX turbos are not specifically built for small nissan engines, they could be performing perfectly fine on some thing like a XR6 turbo.

[Rolls]

so what is the point of the GTX then?

is it jut a big fail on garret's behalf? or is there actually an application where they are superior to the GT range?

Looking at the flow maps it is very high boost applications where it will excel

[ARTZ]

thats another good point Stao I also think they will have been designed for the new gen 21st century engines

[GTScotT]

Yeah, it is true 1Js all have tiny ports.. But each to their own, we can all hold our own opinions to what works best etc. They are not power shy, so I do not think it will change much when considering what the said turbo is capable of.

The other comments regarding the point of the GTX range I cannot argue with.. Just like in the EFR thread, BB cores were debated as a marketing ploy, I feel the same for the GTX range and cannot believe the hype people on this forum are creating by recommending GTX3071s left right and centre.

Again it is an each to their own scenario in my eyes, I do not find the GTX range attractive yet Im sure someone does.. Which will end up being the pioneer for the turbos future rep. I dont think its fair to recommend such an item without any experience with it, and I would regret having done so myself in the past.

Anyway.. Back to exploring Jakarta.

[Rolls]

Sorry to hijack; just dont get this -again a MONSTER torque figure close to 1300Nm, yet I see many skylines with very similar mods making in the 500-600Nm range in the RB25 dyno thread???? Mine made 545Nm and 186rwkw on stock turbo 12psi with supporting mods and I was doubtful of the torque figure as I think it was too high... people with twice as much power have made barely more torque than that, yet there are other people with huge torque figure in the 800-1000Nm range.. anyone care to pour a bit of light on this?

It isn't measuring engine torque that is why, all depends how the dyno is set up

[wolverine]

The GTX3071 looks the pick with the wider islands but if it doesn't perform any better than a garden variety 76mm GT wheel then why spend the extra coin.

I think most of us where expecting GT3076 like power with earlier spool from the 71mm GTX wheel.

Personally I would not have chosen the GTX3076.

[ARTZ]

ditto....not for 270kw anyway..

[ARTZ]

more importantly what boost is it running to get 270?

[simpletool]

Well going from the tech specs it would indeed look like the GTX3071 would be perfect for an RB25. It appears to be made for a 2.5L engine.

The island is fattest at 2.5 pressure ratio (about 1.1-1.2bar intake pressure), and goes from 210 to 550lb flow. This should match the 60mm turbine wheel very well.

I've got to look into this further. If only they made a 0.7 housing option with a bigger waste gate and sectioned it off (ala GT2835 style).

Edited June 20, 2011 by simpletool

[Jap_star]

more importantly what boost is it running to get 270?

he said 17 psi earlier in the thread

[The Mafia]

I what how a GTX3076 at around 20psi would be like on a RB26\30?

Maybe that would be a better match than a RB25?

IF these turbos make more torque then maybe they are more sensitive to capacities.

Oh, and to stir you all up, here is a comparison:

Stock RB25, GT3076 (GT3037), 0.63 turbine housing, 0.6 comp cover, 18psi

This tune took me one hour, I later smoothed out all the bumps. (did a quick tune before a dyno day)

And here is an earlier one:

I love the way the torque curve gets up and stays up, and owns anyones ass in the car.