Jump to content
SAU Community

Recommended Posts

Have done a search and couldn't find much info about anyone trying a GT3271 as a upgrade for a RB25, is it no good am i missing something?

Would it be suitable for someone who's car is 100% street driven.

Turbine A/R can be either 0.78 or 0.69 (wastegated)

Anyway here is the comp map.

Link to comment
https://www.sau.com.au/forums/topic/168368-garrett-gt3271-on-a-rb25/
Share on other sites

Bit of an oddball looking thing isn't it! I don't think it would fit on a stock manifold to be honest.

Potentially it could be very good with the right manifold (split pulse), but it is still plain bearing, and the turbine is probably a touch on the large size for the compressor.

You'd be better off with the ball bearing 3071 in a .63 IW housing IMHO ( the proper 56T 71mm comp and 60mm GT30 turbine), or one of the ATP twin scroll rear ends if you really want a split pulse housing.

It does look an oddball. I've looked at this unit before, thought it was probably best suited to a larger capacity/lower revving engine not chasing bucketloads of power but looking for linear delivery. Perhaps something like a Falcon or Commodore running mild boost.

Turbine efficiency and flow capacity data provided by Garrett does not look fantastic, but the T3 flange means it should bolt on to a stock RB25 manifold.

I tend to agree with BHDave. The GT3071 with 60mm 84T + .63 IW housing is probably a far better option, but if you want zippy immediate low-down response then any of the three trim options in a GT2871R based high flow would do the job quite nicely.

FWIW, you should definitely look at the split pulse option 3071 available from ATP or full-race.com and check the price/availability.

Edited by Dale FZ1

Yeah i knew it looked weird just tryin to be a tightarse, only $1100. I suppose that is expensive if it is not suitable.

Twin scroll GT3071R looks great but i think it maybe to big. As I am after low to midrange power. Shame GT2871R doesn't come in T3 Flange.

Does ATP make a twin scroll turbine housing for the GT2871R as i feel that would be ideal.

Check ATP's website, but that's the only one I could see.

Check hp-inabox because it seems they might have access to OE replica housings as an alternative to getting your own unit high flowed. All of the 2871 cartridges are good in their own right, and you can choose a spec that meets your performance needs in the 220-240 rwkW range, with zippy performance.

The major difference between this option and the big brother 3071 would be in the very bottom end 1500-2500rpm and top end 6000-7000rpm ranges. Better breathing up high will yield stronger power at lower boost without it tapering nearly as noticeably, but I doubt you'd get that zippy/flexible response down low from the 3071.

There MAY be split pulse options from other manufacturers, if that is something you really want. Might be worth a search, and let us know?

Edited by Dale FZ1

Garretts GT3267 and GT3271's are not bad really for a plain bearing turbo and it looks like the more modern centre section than the old T3 and small shaft T4 turbos had .

They are availabe with a couple of different compressors and the 71mm I think using the 71mm GT35 series (BCI-18) family . If thats the case its basically a plain bearing version of the wheel that the GT2871R 52T and GT2835 52T use . Wheel backspacing and bore size are different for BB vs plain bearing cartridges . If you look at the compressors from some GT BB turbos you'll notice they have a hexagon behind the compressor lock or jamb nut . This is because when used in a ball bearing cartridge they were modified from the plain bearing form . In plain form they generally have a threaded bore and the hexagon is used to screw up and tighten the wheel on the turbine shafts thread . BB spec turbines usually have a smaller diametre where the wheel lives and fixed with a locknut so most but not all of the original hexagon gets machined away . With backspacing ball bearing spec wheels can sit closer to the shorter BB bearing housing because there is no need to allow space for the non existant plate/collar thrust bearing . The BB wheel just has a bit more off the back and a smaller plain hole through the guts , spot face the outer end for the nut to bear on and toss it on a BB cartridge .

I'm not certain but the turbine is probably an early diesel design . If you search GT32 turbos you will find that people in the US have played with them on some Subaru engines and a few others . There are dyno plots of the 67mm vs 71mm compressors although they speak of them in terms of pounds (pounds of airflow capacity) .

I wouldn't get too excited over the wastegated housings because I'm pretty sure they only vent one side of the divided housing so no good for a petrol app . As a cheap twin scroll external gate turbo they're probably not a bad thing on an RB25 though I'd prefer the Nissan/Garrett style T04B compressor cover (two bolt in / 3 bolt out) to make it a bit more compact .

The .78 A/R twin scroll non gated turbine housing looks a lot like the one turning up on real GT3071R's and real GT3076R's doesn't it ?

Cheers A .

I agree discopotato the non-gated housing does look familiar.

might be a good thing on GT3071 or GT3076

Anyway looked on hpinabox website and decided that one of their GT2871R with nissan hotside is what i need.

The wastegated turbine on the GT3271 seems to be quite similar to KKR offerings me thinks that these turbos use a turbine housing based on a diesel design. Does anyone think that the GT3271 maybe better that the KKR 430. Just a thought.

Thanks Guys.

I agree discopotato the non-gated housing does look familiar.

might be a good thing on GT3071 or GT3076

Anyway looked on hpinabox website and decided that one of their GT2871R with nissan hotside is what i need.

The wastegated turbine on the GT3271 seems to be quite similar to KKR offerings me thinks that these turbos use a turbine housing based on a diesel design. Does anyone think that the GT3271 maybe better that the KKR 430. Just a thought.

Thanks Guys.

Dale FZ1 has this setup and got some excellent results with it, I suggest you speak with him regarding a few things. He's full of ideas, and is highly knowledgable and motivated in this area.

Anyway looked on hpinabox website and decided that one of their GT2871R with nissan hotside is what i need.

What turbo is this and how much is it?? I've been tossing up between a GT3040, or GT3076 with the .63 exhaust housing. What horsepower rating is this turbo and is it ball bearing??

I am between those 2 because i was told i can achieve the same power with less boost and the same lag with the GT3040 as apose to the GT3076. Just interested about this one now? Pros and cons between the 3?

Actually the modern equal (ball park) of the GT3271 would be the real GT3071R cartridge no 700177-5023 . I believe the same family compressor but in 56 rather than 52 trim . The GT3071R (real one) uses the 60mm 84 trim GT30 UHP turbine where the GT32 is from memory an ~ 64mm diesel design maybe HP series .

Virtually everyone who's used the .78AR twin scroll turbine housing on the real GT3071R raves about the result , gotta be something in it .

Cheers A .

Thanks mate i'll definatly look into it,

I seen this from horsepoweinabox and it directly refered to the rb25det's. I've posted it just recently but i chuck it in here just for the hell of it since im replying anyway

The GT3037/3076 is an exceptional turbo for its HP range. It features a .6 surge slotted comp cover and a complimenting turbine/comp wheel ratio, making it a great bolt on upgrade for the 2-3 litre range engine.

This unit has a lot of flexibility in offered houisings. It can be supplied with a T25 .86 internal housing, a T3 .63 or .82 external gate housing and a recent edition is the option of internal gate T3 in .63 or .82 (these units are more expensive and subject to availability at the time). Usual ultra reliability and superb response from the Garrett ball bearing design.

Great upgrade for RB20/25s and other 2.5-3 litre's looking for some serious power.

Great upgrade for RB20/25s and other 2.5-3 litre's looking for some serious power.[/b]

And the emphasis is on SERIOUS.

Do you want ~ 300rwhp, or ~400?

Response, or power? or a big dash of both. That 3071 would be a great unit, but leave you without the stock-feeling response at the very bottom of the rev range. The 2871 based units will also be great, feeling similar in delivery to stock, just lots stronger. A 3076 won't be to everyone's likes/needs/abilities.

As long as you know exactly what you want out of your car, you can get something that will meet your demands.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
×
×
  • Create New...