Jump to content
SAU Community

GTT or GTS25t ser.1/2 turbo

B0oStEr

By B0oStEr,
in Engines & Forced Induction

 Share

Recommended Posts

R31 POWER Mentor

R31 POWER

Posted
Posted

Well

Series 1 R33 turbo has normal compresser wheel and ceramic exhaust wheel.

Series 2 R33 turbo has nylon/plastic compresser wheel and ceramic exhaust wheel.

R34 GTT turbo is same as above but it might have different guts.

dojobi Experienced

dojobi

Posted
Posted

I'm not so sure the turbo is the reason it makes 206kW, Joel. They've got cams with more lift (from memory) and continuous VVT as opposed to the stepped VVT on the R33. Having said that, I have no idea whether the turbo was actually changed :). I just reckon there are enough differences to explain the extra power.

Cubes Grand Master

Cubes

Posted
Posted

I've heard of them failing on stock boost when they hit the track.

I think turbo's failing (ceramic) has more to do with Exhaust Gas Temp's than anything else.

Pressure probably has a little bit to do with it..

I'll let you know if it is when I get the RB20t turbo cranked up on the RB30DET.

It looks like its going to make at stock boost (11psi) what it made on the rb20det at 1bar. (164rwkw)

I'll dig up this thread if it pops when I try to push a little more boost through it. :)

dojobi Experienced

dojobi

Posted
Posted

Yeah on the track your EGT can certainly get up there and stay up there. My gauge was showing 1100 degrees when I was on the track once. I have no idea where the temp probe was for it though or if that is a high/low reading but it definitely hot enough to kill a turbo I reckon.

An RB20 turbo on an RB30DET will be insane btw. That'll be on boost the second you touch the accelerator.

One other thing - because you have 50% more displacement now, does that mean that the turbo has to flow 50% more air to get the same boost level? So running the same boost will actually be working the turbo harder?

Cubes Grand Master

Cubes

Posted
Posted
An RB20 turbo on an RB30DET will be insane btw. That'll be on boost the second you touch the accelerator.

One other thing - because you have 50% more displacement now, does that mean that the turbo has to flow 50% more air to get the same boost level? So running the same boost will actually be working the turbo harder?

It sounds strange as you let out the clutch and you hear the turbo begin to whistle away before you have even started accelerating... :)

Its not really related to the displacement but more so the head.

The head is what allows air in to the pots and what essentially creates the restriction that creates the measure of pressure.

As the RB25 inlet valves overall are 10mm bigger they obviously allow a higher flow of air before pressure is required to force the air in.

I have noticed with the rb25 that as soon as it makes like 1psi you can feel the extra power. With the RB20 it required around 4-5psi before you really felt anything.

But yer.. the turbo will be spinning harder at a lower psi when bolted on to the rb25 head compared to the rb20t.

This is why Rb20t' need so much boost to make decent power. They have small valves and really look it when you put them side by side to the rb25 valves.

R34GTX Rising Star

R34GTX

Posted
Posted

For the noobs like me out there, what's the tell-tale sign of a failed turbo other than the obvious no boost??

I'd like to know why the GTT turbos fail so often.

Is the failure in the nylon impeller?

It's easy to see how high EGT could transfer heat via the shaft, to melt the nylon impeller.

JAPCAB Proficient

JAPCAB

Posted
Posted

You can always check the turbo for shaft play - this is movement in the shaft of the turbo. You can do this quite easily - remove the intake piping, and then remove the intake pipe going onto the turbo. Check for movement in and out, and side to side. Other tell tale signs can include the turbo being noisy - making loud drilling/spooling noises (we all know a stock turbo shouldnt do this) hitting boost but not being able to hold boost. With the R33 gts-t turbos, they wont last long if run at higher boost levels. With the R34 GTT there seems to be a string of people experiencing turbos failing at .7 bar so probably a good idea to look at replacing the turbo if wanting to run more than stock boost as the standard turbo's dont stand up to that much abuse. Its better to replace the turbo for say $1500 rather than blowing the turbine and risking damaging the engine.

For the noobs like me out there, what's the tell-tale sign of a failed turbo other than the obvious no boost??
Abo Bob Grand Master

Abo Bob

Posted
Posted

I read everything R34 and I don't know where you people are getting this idea that the GTT turbo's are crapping themselves left right and centre.

The ones that I have heard of failing have been the exhaust wheel delaminating and 'ending up in the cat'.

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • foney
      Cheap Gtr For Sale

      By foney · Posted

      BRUH, one of the biggest mistakes of my life..... and i've had plenty ;[)
    • Kapr
      "Cheap" bolt on turbo on RB25DET NEO

      By Kapr · Posted

      @Murray_Calavera iam just considering options 🙂 of course it is very expensive so that why i ask here 🙂  @joshuaho96 I looked at that GCG hybrid(i remember looking at it few weeks before) So this is "that" hybrid where i send them my turbo and they upgrade the inside to Garrett stuff and then they send it back. It cost around 1200-1300 USD which is FAR cheaper than the HKS and it is what iam looking for(i just do not have experience like this...to send something off to "upgrade" ) @tylink720 that is like 150 USD turbo no? 😄 I dont think i have the "ease on my mind" with this kind of turbo. I just put over 7000k USD to "LINK" up my engine...dont want to blow it up with cheap turbo 😄     EDIT: https://www.cj-motor.com/gcg-turbo-charger-for-nissan-rb20det-rb25det-high?srsltid=AfmBOooVeOZ6CZ6r1AIv5m-KPaa6BvudIPJTY8LW78khkd-gQlsaCht9 I looked at this and it seems ok? It is that CGC hybrid and it costs around 1250 USD (with back shipping). Do any of you have experience with this hybrid on NEO turbo? I quickly look thru the forum/web and it seems very good.
    • Rezz
      First time Skyline owner

      By Rezz · Posted

      Echo the awesome sentiment 👍 Definitely a car worth saving. Looking forward to seeing updates as well. 
    • Matt Z
      SAU NSW - Chickos Cruise

      By Matt Z · Posted

      Scenic roads, stunning skylines, and Chickos to finish it off! Join SAU NSW as we cruise through the Royal National Park and along Lawrence Hargrave Drive to Figtree! Sunday 26th October 2025 4:30PM Meeting Waterfall Station Parking 5:00PM Cruise Departure Royal National Park > Lawrence Hargrave Dr > Memorial Dr > Sid Parrish Park 6:15PM Arrival at Sid Parrish Park Figtree Meet Location: Waterfall Station Parking Final Destination: Sid Parrish Park RSVP: https://forms.gle/E4s5SiRKQfDdypky8 *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • MBS206
      "Cheap" bolt on turbo on RB25DET NEO

      By MBS206 · Posted

      It's funny, as Ive seen plenty of people use them in cheap builds on YT. And they actually go okay, even though a lot of other maxspeedingrods stuff is terrible. Those turbos seem reliable enough, the only part being, a good quality turbo that is "identical" to it, will out perform it day in and day out. In both a lower boost threshold, and the ability to flow more air at the same boost pressure. As a cheap cheap replacement, not a terrible choice. For cheap and shouldn't blow in a day, not terrible (like other eBay/Temu turbos) for low cost and still decent performance, that's where the question comes in to play from the results I've seen. I'd actually find it hilarious to buy one, and strap it to a paddock basher or some other cheap as POS originally NA car, and send it to the moon!
×
×
  • Create New...