Jump to content
SAU Community

Recommended Posts

I remember reading somewhere that there were a couple variants of the HKS GT2530's as well as the KAI model. I'm assuming this means HKS updated them along the way, does anyone know if this is true and if so what are the difference and how could each be identified?

Any info would be greatly appreciated

Link to comment
https://www.sau.com.au/forums/topic/451492-hks-gt2530-variants/
Share on other sites

all share the same CHRA/wheels except the kai.

Housings differed like mentioned.

RB26 housings also differed mainly on exh side, early had no splitter late had a splitter on the outlet that was flush to the outlet flange. Apart from that some minor gate differences

No real power difference if your using a 1-1.5'' wastegate separator in a bellmouth

They should all be using the same cartridge and wheels 446179-21 from memory . I seem to remember the KAI version having a port shrouded compressor housing so was likely a single turbo version . The main unique part today is the 60mm 63T compressor wheel and I think it was only ever used in 2530s and one other app I can't remember .

You can turn any GT2860 with the same turbine into a 2530 if you have the original undamaged compressor wheel and housing . Swap the wheel in balance and bingo new guts .

A .

I remember reading somewhere that there were a couple variants of the HKS GT2530's as well as the KAI model. I'm assuming this means HKS updated them along the way, does anyone know if this is true and if so what are the difference and how could each be identified?

Any info would be greatly appreciated

why do you ask? perhaps if we had a bit more info on the specifics of what ur trying to find out it would help...

why do you ask? perhaps if we had a bit more info on the specifics of what ur trying to find out it would help...

I'm gathering parts for a turbo upgrade. I'll be looking for roughly a safe 320rwkw but more power down the track so I'd like to get the right turbos from now, hence why I'm looking at the 2530's. I know -7's or even -9's would be better suited to that 300+ mark but any more power later on will be maxing them out. So I guess at the moment I'm just trying to educate myself on my options.

Just get the -9s.

Sell the -9s if you ever decide to go for 400rwkw and get 2530s in 2/3/4 years (or more) and enjoy the -9s for their application for now because realistically 2530s is motor out/rebuild time anyway. So changing turbos isn't a big expense.

  • Like 1

Might also depend on your demographic, i.e Sydney lots of 40/50klm zones and not much

in the way of over 80klm higher load gears, a few hundred rpm of boost threshold and

less off boost power can make driving around on bigger turbos tedious.

The opposite if you live in an area with lots of open roads or highways. I.e rural or

the US. You can get away with larger turbos since you are mostly above 80klms with

very little time spent in stop start traffic and low speed pot holed filled corners,

stupid 40klm school zones with not a single kid in sight. In this case you can go

for the -5 or 2530's and just not spend enough time off the boil to care.

End of the day, it still comes down to drivability first as the main consideration

on size, then peak power goals.

I will tell you my experience. I had a unopened motor with -5's and they were a little laggy (running 345kw atw) but on the open road they are great. In the city not to much (as above).

When I rebuilt the motor and did head work now pushing 400kw the -5's have come alive. Still running 2.6L and they are more than fun anywhere haha. I wouldn't waste money getting 2 different sets of turbos (selling one for a loss later) if you plan to rebuild. Go for a set you want to keep deal with the lag at first then benefit later when you rebuild. Less cost when you do rebuild.

Also as Jeremy Clarkson said - lag can be fun at the lights when people think they are winning then they wonder where you have gone.

Yeah I do see where you're coming from but would the -9s be that much better than the 2530s for my goal that you can justify doing it twice?

Absolutely. Turbos are the most important thing to choose. They decide everything in a set-up in a stock-ish scenario.
You are talking about $1,200 or so. So like I said if you plan on not rebuilding etc for 2 years or more - then change it out when the time comes.
I've had both -9, -5s and modified -9s... The -5s around town, hill runs, motorkhana etc as stated, are tedious on a 2.6l. -9s win for a car doing that type of work hands down.
-5s come into their own above 120km/h-150km/h+. You just gotta ask yourself how much time are you spending above that? And go from there.

Would HKS GT-SS's be an even better option?
Thanks for all the help guys

Much more research needed. The Garrett -9s and HKS GT-SS are the same turbo, just a different branding. HKS "kit" just comes with everything you need to bolt on, oh and a much higher price tag.

For my project the motor will be just one aspect in a sort of complete rebuild with suspension next and ultimately paint and interior so I think what ever set up I go for now will pretty much be it for a while (providing the motor doesn't give up). Having said that though I do miss the punch my 33 GTST used to give so maybe that little bit of lag given by the -5 will be enjoyable but I definitely don't want to have to go 120km+ whilst ringing it's nuts for the turbos to show what they've got. My best bet would be to experience most, if not all of my options first hand.

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


  • Latest Posts

    • Apologies for the long post, but needed somewhere to lay out the entire timeline of events and actions taken:   I've got an 89 GTR with a R34 RB in it. It's been running great all year, driven probably 500KM in the last month. It's not my daily driver, just a weekend fun car.    Build info: R34 RB26 - HKS 2.7 stroker kit, HKS adjustable cam gears, HKS turbo upgrades, Trust intercooler, R34 factory DENSO 440cc injectors, JUN chipped/tuned R32 ECU. All of this work was performed in Japan back in 2019.    Thursday 10/2/25 - It's a nice day and decided I'll drive it to work, I start it up in the garage and I notice it took a few extra cranks and sounded a bit funny. I figure maybe it was just because it was a pretty chilly morning. I pull it out into the driveway to warm up a bit before leaving. As I leave the driveway, it feels very off and sounds like a misfire. I pull it back in the garage to deal with after work and take the daily to work. I was able to diagnose it as a cylinder 5 misfire with the old spark plug test (unplugging each plug until a sound change with the engine running). I take off the whole ignition system, ignitor, plugs, spark. *Important note, it is still on the R32 ignition system with the separate ignitor system. I test each system with a multi-meter and nothing presents as a smoking gun. I put it all back together and it starts up no issue. I go ahead and order the PRP R35 ignition conversion kit. It should arrive today (10/13/25)   Friday 10/3/25 - Another nice day, car starts up great and drives great all day. Very pleased that everything seems to be OK   Sunday 10/5/25 - Decided I'll take it to play some golf, load up and drive to the course about 25 minutes away. Drives wonderful the whole way there, I pull in the parking lot and the engine completely comes to a stop. I do not recall if it sputtered at all, but just remember all of the sudden the engine was off. I roll it into a parking spot, try to crank it back on and nothing.  It'll crank and crank and not even try to start. End up getting it towed back to my house and push it up into the garage.    Items I have checked: Fuel in the tank Fuel Pump relay Fuel pump fuse  Spark Plugs & gap Coil packs Ignitor    I know the cylinders are getting fuel as the plugs smell like fuel after a start attempt. I tried spraying starter fluid into the manifold and cranking and not even a sputter.    I decided to do the live CAS test (removing the the CAS, ignition on and spinning the CAS stalk to see if the injectors pulse and spark is active). All of the injectors were pulsing and I have spark at the plug. The half-moon end of the CAS did seem very loose, I'm not sure how much play is supposed to be there, but it was more than I expected. There was no in/out play of the shaft, just the tip end that is pinned on had quite a bit of play.    CAS Play video   When I put the CAS back in, I stupidly did not re-time the engine. I know I need to do that tonight, however, I do not think it will start given it seemingly was not the issue. My plan is to do the PRP R35 coil kit and retime the engine at the same time.    I plan on ordering the Haltech Nexus Plug-in ECU once they are available again, but ideally would like to get this sorted before firing the parts cannon at it and potentially adding more variables.    Anything glaring that I am missing here, I'm a bit at a loss?          
    • Get it on a dyno. Get something logging Consult. Run it up and find out what is causing it.
    • Looking for a plenum for rb25 de+t neo  Not looking to push much power maybe 300kw at the wheels, is there much difference in flow for Freddy “Greddy style” compared to original Greddy or options like Proflow or Otaku garage?    I won’t be porting the de Neo head for now as I think it’ll be fine 280-300rwkw but appreciate the help and any experiences anyone has between them and any advice. Thanks  Looking at this plenum for now below 
    • engine wise almost no mods: stock ecu Greddy front mount intercooler Greddy forward facing intake w R33 TB stock fuel system, stock injectors, rail etc. Kakimoto racing hyper 3 inch exhaust system Apexi intake filter New NGK –R BCPRES (.8 gap) plugs  
    • Nice one @Pac - looks like a fair few 1600's there! 
×
×
  • Create New...