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Ok guys..... Be patient ok :D

Those ceramic fu@#ers has me reallllly bummy on the 26 , so i was weighing out the cost of changing them to a set of steels (garrett equivalent to gt-ss) or slapping on some extra gear to the perfectly good 25det i have sitting in my garage, and put it back in.

One of the main factors too is that 26 parts here(not in Aus) are verry hard to get,and when u do find them,they are extremely exp. The 25 on the other hand has parts readily available.

If i sell the 26, the cost of getting turbo/injectors/ecu for the 25 will be about the same with some left over to do the ex, lines for the turbo,piping etc.

Where as if i sell the 25, that would only cover half the cost of getting the steels for the 26 alone.

I will be adding a water/meth inj. kit no matter which set up i use, as our best brew is 95.

So here are the specifics:

Rb26dett--- Stock ecu / GT-SS equivalent / Water meth / Apexi pods / Cam gears / 3" Ex./ stock internals

Rb25det---- Pfc / GT30R -.63 / 555 inj / Water meth / Blitz pod / Cam gears / 3" Ex. / stock internals / stock ex. manifold

Now the important part..... I am aiming for a very responsive streeter as it is my daily driver, up to roughly 260-280rwkw.

Out of the two above combinations which will be the most responsive, and an overall better performer?

Thanks again.

Stock ECU = loose. Plus as you said, parts prices, forget the 26 IMO. Stock 26 ECU isn't bad, but really you dont want to use i.

Plus if you only want 260rwkw, GT-SS's are even too big for that, stock turbo's (with steel wheels) will do what you want there if you go that road

25 with a 3071, not the 3076.

Actually aiming for 280kw, but if i get 260kw,i'll live with that.

Unfortunately, no one to rebuild stock items with steel wheels here.

Still doing some reading up on the turbo chioces for the 25

When i had the 25 in, i read almost all the threads concerning these said turbos.........I guess i'll have to read them again. :D

nope Trust... as you say "I am aiming for a very responsive streeter as it is my daily driver" so go with the RB25... VCT, high comp and long plenum runners make it a much better street motor... if you were looking at higher power I would say go for the 26 but at for mid-high 200's Rb25 all the way... plus as ash said PFC is the way to go

Most likely i will be using a garrett item as there is an authorized dealer here, and i don't see many HKS / Greddy units unless it comes used through importers, which is verrry rear as the japs tend to keep this sort of gear.

To tell u the truth, i was bit disappointed when replaced the 25 with the 26 in terms of lag and response. The 25 using the 20 actuator had instant full boost(11psi) from as low as 2500rpm which made the car fun to drive,considering it has the weight of a bus!

With the target power of 280rwkw, i don't want to breaking traction too much though, because when her big a$$ starts sliding it kinda hard to bring back....yet ,response is the aim of the game :thumbsup:

Hasn't garrett brought out the GT3076r (GT30R) with a 52 trim comp yet?

Most likely i will be using a garrett item as there is an authorized dealer here, and i don't see many HKS / Greddy units unless it comes used through importers, which is verrry rear as the japs tend to keep this sort of gear.

To tell u the truth, i was bit disappointed when replaced the 25 with the 26 in terms of lag and response. The 25 using the 20 actuator had instant full boost(11psi) from as low as 2500rpm which made the car fun to drive,considering it has the weight of a bus!

With the target power of 280rwkw, i don't want to breaking traction too much though, because when her big a$$ starts sliding it kinda hard to bring back....yet ,response is the aim of the game :huh:

Hasn't garrett brought out the GT3076r (GT30R) with a 52 trim comp yet?

For what its worth, a guy in my area put a 56Trim GT30R on his 4WD Neo RB25 Stagea and is making 270awkw at 17psi with it and absolutely loves it. Its making 17psi by around 3700rpm and can lose all wheel traction giving it a boot full, by all accounts its a heap of fun for a bus.

You couldn't give me twin std posie bush bearing turbos or the RB26 to hang off them . Just BS work and money to pull the car apart and rebuild plain bearing turbos when they go cough - smoke screen . And they do .

I think sensible people rip bush turbos off and fit BB ones to keep them alive on RB26's .

The question you need to ask yourself is will the GT3076R'd RB25 come on boost before the RB26 will because if it does it will start hauling sooner .

Personally for drive it every day duties the hydraulic bucket 25 is easier and less costly to live with than a shim/mechanical RB26 . Also if the 3076R fell over you going to be up and running a lot sooner and for less money than the 26 if the glass turbos let go .

A .

The question you need to ask yourself is will the GT3076R'd RB25 come on boost before the RB26 will because if it does it will start hauling sooner . [

This is the question i need the answer for! :blush:

Geeze....can't seem to figure out how to use this quote function :)

Edited by smell
  • 2 months later...
When i had the 25 in, i read almost all the threads concerning these said turbos.........I guess i'll have to read them again. :(

Wwoooowwww..... Finally finished reading all those "Rb25 turbo upgrade" threads again!!!

So for the 260-280rwkw region i see the GT3071 is capable with an average of 20psi and the GT3076 with an average of 18psi

I am however leaning towards the genuine Gt3071 .82 as i have seen "skylinecouple" have good results with it although he might be the only one who tried this combo!???

On that note "skylinecouple" did you ever sort out the dump pipe issues, and do u have a dyno chart with boost against rpm???

I am very impressed also with the results of the GT2835pro S but alot of guys are not stating what size the turbine is, so its hard to make a conclusion.

"The Mafia" had some good results too with the GT3076 .63 but i think 300kw might be a little too much for me BUT..... if this set up is more responsive than "skylinecouple" GT3071 .82 i don't mind going in this direction either.

The GT3071 .63 is totally out of the question because even with the Garrett .63 housing i see there are issues with boost control.

So.... at the end of the day, is there anyone who have driven or seen any cars with these set ups peform???

I'm intrested mainly on response, and would really like to know the real world differences between the Gt3076 .63 and the Gt3071 .82 Garrett on a basically stock Rb25det.

Also is there anyone else who have tried this original Garrett Gt3071 .82 combo??? Pls share your experiences.

Dyno sheets appriciated :P

Ooooh... and it MUST be more responsive than a stock Rb26dett with 14psi, which by the way i think sucks..... 14psi by 3800rpm in 4th

if you have the 26 already installed, go gt3076 with a remapped std ecu, the gtr has a really nice std ecu and comes up killer with a remap. I'm nearly convinced the remap in a gtr is better than a afm PFC.

Nah, i'm gettin rid of the 26...... most likely :D

Parts are too hard to come by, and the price i could sell it for i would be able to get turbo/injectors/pfc/exhaust work etc. done for the 25det i already have taking up space in my garage.

The million dollar question though is will the 25 be more responsive and powerful than the stock 26 with one of the two above turbo choices...ie. Garrett Gt3071 .82 or Gt3076 .63

the answer to the million dollar question is yes

with a 3076 .82 rear my 25 made 309rwkw at 18psi and made the 18psi by about 3800rpm. the 3071 would be better again and make your powere requirement no worries

stock manifolds, poncams and a built engine, but it was lower compression ratio than stock so that would have hindered response rather than helped

Was your stock manifold power ported/extrude honed?

stock manifolds, poncams and a built engine, but it was lower compression ratio than stock so that would have hindered response rather than helped

Nice result but i will not be using any cams just an adj ex cam gear

May be it was because of the cams u got full boost so early???

Just concerned about boost control with the small back end (.63) on the Gt3076, but i feel it might make the 260-280rwkw a little more "safe" than running the Gt3071 .82 to it's limit...or close to anyway.

Response.... response.......response......

Oooooh.... found "skylinecouple" Dyno sheet ...... 18-19psi by 3800rpm Gt3071 .82 ......nice

I just f#@kin hate dyno sheets with kph and not rpm!!!

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