# HKS GT III turbos : Annyone using them?



## Zenki33 (Apr 6, 2014)

Hello,

I came across these "new" turbos from HKS GT III series. They appear to be fitted with billet compressors? Does anyone know specs on these turbos or if anyone is using them in their RB26/28?

I'm thinking to migrate from 2860-9's to -5's due the stroker 2.8L I'm building but this option might be worth to look?

SPORTS TURBINE KIT | TURBO | PRODUCT | HKS


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## matty32 (Dec 18, 2005)

I posted these the other day

I may go this route over the tomeis


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## t5syy (Sep 30, 2014)

I saw the hks advert they look good. How much are they? Are they Std mount or top fit ?


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## FRRACER (Jun 23, 2013)

Cannot justify the cost at over £3k and also on a 2.6 and even 2.8 they appear laggy when compared to the 2530 with only a little more top end.. Save your money and buy a set of -5 turbos.


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## matty32 (Dec 18, 2005)

Stock fitment as per pic above 

Il work out prices but im heading to tokyo right now


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## FRRACER (Jun 23, 2013)




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## GT-R David (Mar 13, 2013)

All the Dyno sheets only show the GT III-RS.
Would be really interesting to see more about the GT III-SS.


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## GTRNICK (Apr 29, 2005)

Your better off buying a second hand set of gtrs or 2530s


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## FRRACER (Jun 23, 2013)

As said better off buying a set of 2530 which Nick has for sale at a good price. New spec -5 are a noticeable improvement over the older spec.


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## GTRNICK (Apr 29, 2005)

FRRACER said:


> As said better off buying a set of 2530 which Nick has for sale at a good price. New spec -5 are a noticeable improvement over the older spec.


Thanks dude.:bowdown1:


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## FRRACER (Jun 23, 2013)

I would have bought them myself but too many other things tied up the cash at the mo.


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## GTRNICK (Apr 29, 2005)

FRRACER said:


> I would have bought them myself but too many other things tied up the cash at the mo.


Well I ain't in any rush as they ain't going down in value :chuckle:


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## Zenki33 (Apr 6, 2014)

GT-R David said:


> All the Dyno sheets only show the GT III-RS.
> Would be really interesting to see more about the GT III-SS.


What are the differences between the RS and SS variants?

Also, the HKS 2530's are a tad larger than the 2860-5's correct?


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## FRRACER (Jun 23, 2013)

Differences are very small.


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## GTRNICK (Apr 29, 2005)

Zenki33 said:


> What are the differences between the RS and SS variants?
> 
> Also, the HKS 2530's are a tad larger than the 2860-5's correct?


Look minimal on that chart but will.be slightly noticeable on the dyno or right foot. Broader band.


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## matty32 (Dec 18, 2005)

t5syy said:


> I saw the hks advert they look good. How much are they? Are they Std mount or top fit ?


Rs kit is 3k

The gt3 ss kit is about 300 cheaper

Article this month on the Hks street performer gtr sporting them 
(Street and track article)

Least Hks now do a bolt on turbo option for gtr (twins)


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## CT17 (Mar 25, 2011)

Ron at RK has my previous set of -5s with billet wheels if anyone wants them.
They were great but I wanted to try the twin EFR kit.


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## Zenki33 (Apr 6, 2014)

matty32 said:


> Rs kit is 3k
> 
> The gt3 ss kit is about 300 cheaper
> 
> ...


3k for BOTH turbos correct?


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## matty32 (Dec 18, 2005)

Yes if you want a set just pm


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## peckhs (Jul 20, 2013)

I was considering this set of turbos for my new engine, but as FRRACER stated, it might be better to get the GT2530 instead... so I am hesitating
btw, pardon my ignorance. What is -5 turbo? garrett??


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## Zenki33 (Apr 6, 2014)

matty32 said:


> Yes if you want a set just pm


That price includes WG's?


I'm building a 2.8L HKS but nothing wild.


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## GTRNICK (Apr 29, 2005)

Zenki33 said:


> That price includes WG's?
> 
> 
> I'm building a 2.8L HKS but nothing wild.


What power are you looking to achieve?


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## GTRNICK (Apr 29, 2005)

peckhs said:


> I was considering this set of turbos for my new engine, but as FRRACER stated, it might be better to get the GT2530 instead... so I am hesitating
> btw, pardon my ignorance. What is -5 turbo? garrett??


They are basically a garrett equivalent of a 2530 with possibly a tad more response and less mid range top end power.

I think for the 550hp to 600hp range the hks 2530 is a hard turbo setup to beat till this day. I love them but for my 3ltr they were too small. Perfect for a 2.6ltr to 2.8ltr.


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## Zenki33 (Apr 6, 2014)

GTRNICK said:


> What power are you looking to achieve?


Looking to get 600-650 crank HP with good response. Already fitting Tomei 260 10.25mm lift with full exhaust and no CAT.


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## GTRNICK (Apr 29, 2005)

Zenki33 said:


> Looking to get 600-650 crank HP with good response. Already fitting Tomei 260 10.25mm lift with full exhaust and no CAT.


Nice cams on a 2.8 I'd even go 272.

2530 can achieve just over 600. But the gt3 rs will give you 650 plus.


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## Cris (Sep 17, 2007)

peckhs said:


> I was considering this set of turbos for my new engine, but as FRRACER stated, it might be better to get the GT2530 instead... so I am hesitating
> btw, pardon my ignorance. What is -5 turbo? garrett??


Judging by the graphs I'd say the 2530 is a better bet. Loose a little top end to gain low / mid.

As above -5s are essentially the same as 2530s. Supposedly you can improve the -5s with the newer GTX tech but I don't know how much difference this would make (perhaps even this is what the new HKS turbos represent).


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## peckhs (Jul 20, 2013)

GTRNICK said:


> They are basically a garrett equivalent of a 2530 with possibly a tad more response and less mid range top end power.
> 
> I think for the 550hp to 600hp range the hks 2530 is a hard turbo setup to beat till this day. I love them but for my 3ltr they were too small. Perfect for a 2.6ltr to 2.8ltr.


Thanks GTRNICK.
That's what i was told.
I am making about 450whp on my 2.6L now, and that's limited by the HKS GT-SS I have in the car currently.
I am looking for about 600whp with the new Tomei that I have, that's why was looking forward to the GT3RS initially..
Having doubts now after seeing the test run results..

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## GTRNICK (Apr 29, 2005)

peckhs said:


> Thanks GTRNICK.
> That's what i was told.
> I am making about 450whp on my 2.6L now, and that's limited by the HKS GT-SS I have in the car currently.
> I am looking for about 600whp with the new Tomei that I have, that's why was looking forward to the GT3RS initially..
> ...



I just don't think for 600hp there is a better choice than 2530. Apart from the garrett.

Gt3 rs are just an expensive garrett equivalent. Paying for the name.


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## peckhs (Jul 20, 2013)

GTRNICK said:


> I just don't think for 600hp there is a better choice than 2530. Apart from the garrett.
> 
> Gt3 rs are just an expensive garrett equivalent. Paying for the name.


I don't think the 2530s are available new now

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## GTRNICK (Apr 29, 2005)

peckhs said:


> I don't think the 2530s are available new now
> 
> Sent from my SM-N910G using Tapatalk


No but I do have set for sale with hks turbo elbows. I bought the car with them.running 1.4bar on high and 1 bar on low.

The car made 533whp at just under 1.4bar. So if pushed to 1.6 bar I reckon over 550whp.


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## matty32 (Dec 18, 2005)

There's a review in full in gtr mag today 

Hks 33 running them now


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## GT-R David (Mar 13, 2013)

Can you upload some high quality pictures from the complete article?


I think they are journal bearing Turbos?


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## matty32 (Dec 18, 2005)

GT-R David said:


> Can you upload some high quality pictures from the complete article?
> 
> 
> I think they are journal bearing Turbos?


Sorry ..I do t have a scanner here to use


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## Zenki33 (Apr 6, 2014)

Wonder what they say in that article


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## Chris_Gojira (Oct 1, 2012)

Let's get some things straight here.

- 2530's are perfectly available new
- HKS turbo's are not a Garret copy, or even an adjusted Garret Turbo, they are developed in-house.


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## peckhs (Jul 20, 2013)

Chris_Gojira said:


> Let's get some things straight here.
> 
> - 2530's are perfectly available new
> - HKS turbo's are not a Garret copy, or even an adjusted Garret Turbo, they are developed in-house.


I would be very interested to know where I can still get brand new 2530s. I have asked the retailers but everyone told me they have been discontinued. 
Thanks.

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## Chris_Gojira (Oct 1, 2012)

Very sorry, misread the type. I meant Garret 2860! scuzie scuzie


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## matty32 (Dec 18, 2005)

peckhs said:


> I would be very interested to know where I can still get brand new 2530s. I have asked the retailers but everyone told me they have been discontinued.
> Thanks.
> 
> Sent from my SM-N910G using Tapatalk


They are discontinued from Hks


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## peckhs (Jul 20, 2013)

No worries...
Although i was a little excited for a while... 

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## tarmac terror (Jul 16, 2003)

peckhs said:


> No worries...
> Although i was a little excited for a while...
> 
> Sent from my SM-N910G using Tapatalk


You could always find a pair of cheap, knackered ones and have them rebuilt!!


TT


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## RBnutz (May 7, 2012)

They use thrust bearings.

GT III SPORTS TURBINE KIT?SKYLINE GT-R

GT III SPORTS TURBINE KIT?SKYLINE GT-R


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## peckhs (Jul 20, 2013)

I have a question.
I was told if i was to use a gtss with a rb28 there will be choke..
If i am looking at 500bhp, is the gtss a suitable turbo or i should consider something newer like the gt3ss?

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## Zenki33 (Apr 6, 2014)

RBnutz said:


> They use thrust bearings.
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R


What??



> Whilst this is a thrust bearing type turbo, high response compatible with ball bearing setup has been achieved



:runaway::runaway::runaway::runaway::runaway:


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## GTRNICK (Apr 29, 2005)

peckhs said:


> I have a question.
> I was told if i was to use a gtss with a rb28 there will be choke..
> If i am looking at 500bhp, is the gtss a suitable turbo or i should consider something newer like the gt3ss?
> 
> Sent from my SM-N910G using Tapatalk


I would use something similar to the new gt3rs or 2530 as a minimum.

GT ss is too small.

I had 2530s on a 3ltr and they were very responsive but just too small.


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## peckhs (Jul 20, 2013)

Noted witg thanks GTRNICK 

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## tarmac terror (Jul 16, 2003)

RBnutz said:


> They use thrust bearings.
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R


Who, in their right mind, would dump £3k on these???
That's just insane....and for what!!??

You could easily spend less than HALF that on different turbos and achieve similar results..

But then, I suppose you don't get to show off the amazing HKS branding to your mates..



Go figure...?



TT


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## GT-R David (Mar 13, 2013)

RBnutz said:


> They use thrust bearings.
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R
> 
> GT III SPORTS TURBINE KIT?SKYLINE GT-R


Thanks for the link.

Again not the turbos I was hoping for...
Need one with the response of a GTSS (-9), but with a little bit more top end.

GT3SS have less top end but a little bit more response if we look at the curve from the link above. Better buying -7 instead of them.


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## FRRACER (Jun 23, 2013)

Bit of a backward step going thrust bearings.


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## FRRACER (Jun 23, 2013)

tarmac terror said:


> Who, in their right mind, would dump £3k on these???
> That's just insane....and for what!!??
> 
> You could easily spend less than HALF that on different turbos and achieve similar results..
> ...


Matty32 would :chuckle:


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## AlexJ (Apr 3, 2003)

FRRACER said:


> Bit of a backward step going thrust bearings.


i noticed the tomei twins are also journal bearing. BBs are not as big a deal as they used to be for response with better design/aerodynamics these days, and journals are much cheaper to service/rebuild. still for the money these hks twins dont seem to make sense compared to a good modern single esp.


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## FRRACER (Jun 23, 2013)

A thrust bearing will always have more inherent friction compared to a steel ball bearing setup and now we're seeing more with ceramic ball bearings to reduce friction further


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## AlexJ (Apr 3, 2003)

FRRACER said:


> A thrust bearing will always have more inherent friction compared to a steel ball bearing setup and now we're seeing more with ceramic ball bearings to reduce friction further


yeah but if you can get most of the response with journals as with bbs then there is less justification for added initial and service costs. taking two turbos with the same specs, like for like, bbs vs journal, bbs win for sure, but if you can find a journal turbo with the same response as the available (more expensive) bb options why spend the extra?


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## Cris (Sep 17, 2007)

GT-R David said:


> Thanks for the link.
> 
> Again not the turbos I was hoping for...
> Need one with the response of a GTSS (-9), but with a little bit more top end.
> ...


As I read it the new items come on a touch later than 2530s but have a touch more top end


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## FRRACER (Jun 23, 2013)

Alex I cannot think of why anyone would buy these turbos. At £3k plus they are more than double the price of Garrett -9 and -5 which have recently been upgraded to metal cages and ceramic bearings. One would have to be clueless to buy this setup considering the market is dominated by quality ball bearing turbos.


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## GT-R David (Mar 13, 2013)

Cris said:


> As I read it the new items come on a touch later than 2530s but have a touch more top end


Yes, the GT3RS do this over the 2530

But the GT3SS have a touch less top end than the GTSS/2510/Garrett-9 Turbos

No p&p turbo upgrade is the other way

About the price, as far as I remember, the GTSS Kit from HKS also was around 2.5k
Remember it includes all necessary gaskets. Still more expensive than buying Garrett -9 and original Nissan gaskets.
But this time it isn't the same turbo as a Garrett. If it would meet my requirements for a turbo, I woudn't give a shit about the price.


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## AlexJ (Apr 3, 2003)

FRRACER said:


> Alex I cannot think of why anyone would buy these turbos. At £3k plus they are more than double the price of Garrett -9 and -5 which have recently been upgraded to metal cages and ceramic bearings. One would have to be clueless to buy this setup considering the market is dominated by quality ball bearing turbos.


I agree these new hks kits don't look competitive in the current market. As long as -7/9s and -5s are available they are a no brainer really for low mount twins.

my point was about journal vs bb in general. I used to discount journal turbos, but things have moved on. I wouldnt discount these hks kits purely because they are journal, but they are too expensive and the performance doesnt look that special at all.

As for who would buy the hks kits, plenty of people no doubt, and they'd probably be very happy with them, that £1500 price difference is not all that much to many people, and the hks kits have always been dear. Still, factor in the cost of a simple rebuild on a journal vs a re-core for a bb and that price difference narrows a fair amount in terms of TCO - not enough though.


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## peckhs (Jul 20, 2013)

Is there a comparison done between the 2530 and -5s?
I keep hearing that the 2530s are superior to the -5s, but i really would like to see a direct comparison like those from HKS for their turbos.

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## GTRNICK (Apr 29, 2005)

peckhs said:


> Is there a comparison done between the 2530 and -5s?
> I keep hearing that the 2530s are superior to the -5s, but i really would like to see a direct comparison like those from HKS for their turbos.
> 
> Sent from my SM-N910G using Tapatalk


Good luck with that.

It's gonna be hard to find 2530's now ive sold mine.

If I were you I'd go for a nice single turbo. Much less headache these days. Or just go for the -5s.


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## GT-R David (Mar 13, 2013)

peckhs said:


> Is there a comparison done between the 2530 and -5s?
> I keep hearing that the 2530s are superior to the -5s, but i really would like to see a direct comparison like those from HKS for their turbos.
> 
> Sent from my SM-N910G using Tapatalk


Lots of information on the Australian Skyline Forum. SAU.


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## RBnutz (May 7, 2012)

Why we are on the topic, does anyone have or know of back to back results of R34N1/-7s vs -9s/GTss ?


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## peckhs (Jul 20, 2013)

Thanks David ( I am assuming that is your name, pardon me if i am incorrect).
I will check SAU.

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## goghat (May 13, 2007)

Can the 2530's be rebuilt ? I've got a set here, but the bearings are making a noise so I swapped them for '5's


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## FRRACER (Jun 23, 2013)

Are you planning to sell them David?


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## AlexJ (Apr 3, 2003)

goghat said:


> Can the 2530's be rebuilt ? I've got a set here, but the bearings are making a noise so I swapped them for '5's


Sort of, they dont rebuild as such, them they just replace the entire chra which is around £500 each turbo iirc

The hks chras may not be available anymore, maybe a stock garret one would work.


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## peckhs (Jul 20, 2013)

AlexJ said:


> Sort of, they dont rebuild as such, them they just replace the entire chra which is around £500 each turbo iirc
> 
> The hks chras may not be available anymore, maybe a stock garret one would work.


GBP500 to rebuild? I think maybe can get a good condition used for that price in japan?
I have seen some going for JPY80000 each.. they looked decent from the photos..
The problem is we can never be sure how good the condition will be..

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## peckhs (Jul 20, 2013)

They state that it is for S14/S15 use ...
Can it be used for the rb26?

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## FRRACER (Jun 23, 2013)

Don't beat yourself up over a GT2530 just get a new spec -5 they are great turbos!


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## AlexJ (Apr 3, 2003)

peckhs said:


> They state that it is for S14/S15 use ...
> Can it be used for the rb26?
> 
> Sent from my SM-N910G using Tapatalk


Nope. HKS made the 2530 kits in single turbo SR20,RB20/25 versions in addition to the twin RB26 version - all different exhaust housings/downpipe flanges.


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## peckhs (Jul 20, 2013)

FRRACER said:


> Don't beat yourself up over a GT2530 just get a new spec -5 they are great turbos!


Hahahah... i am waiting to replace my engine, so i am still considering my options..
How do I tell the difference between the new -5s and the older -5s?


AlexJ said:


> Nope. HKS made the 2530 kits in single turbo SR20,RB20/25 versions in addition to the twin RB26 version - all different exhaust housings/downpipe flanges.


Thanks for the information AlexJ!

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## Cris (Sep 17, 2007)

AlexJ said:


> Sort of, they dont rebuild as such, them they just replace the entire chra which is around £500 each turbo iirc
> 
> The hks chras may not be available anymore, maybe a stock garret one would work.


I bought mine as refurbished units.

TBH I'd happily swap them for the latest -9s but the cost of pulling them off and remapping etc means it's a waste of time.


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## FRRACER (Jun 23, 2013)

peckhs said:


> Hahahah... i am waiting to replace my engine, so i am still considering my options..
> How do I tell the difference between the new -5s and the older -5s?
> 
> Thanks for the information AlexJ!
> ...


836026 prefix for part number


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## peckhs (Jul 20, 2013)

Great! Checking the garrett website now.
Thanks!

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## David (Apr 25, 2003)

peckhs said:


> Great! Checking the garrett website now.
> Thanks!
> 
> Sent from my SM-N910G using Tapatalk


You would be better off pm'ing the guy above his turbos are very competitively priced


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## FRRACER (Jun 23, 2013)

Can supply turbos to you Peckhs PM me if interested.


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## t5syy (Sep 30, 2014)

FRRACER said:


> Can supply turbos to you Peckhs PM me if interested.


Out of interest how much is a pair of new -5 and what boost do they safely run at.cheers


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## EF Ian (Jan 11, 2013)

GT-R David said:


> Need one with the response of a GTSS (-9), but with a little bit more top end.


Thats exactly what I'd want, would like slightly more top end but not at the expense of the response of GT-SS. 

Surely by now there is the technology to create this.


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## RBnutz (May 7, 2012)

EF Ian said:


> Thats exactly what I'd want, would like slightly more top end but not at the expense of the response of GT-SS.
> 
> Surely by now there is the technology to create this.


I'm sure there is. But its in the form of a single. Companys don't bother with these little twins anymore.... apart from the said HKS, which are old tech. 

Do the GT-SS offer this over the -7s?


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## FRRACER (Jun 23, 2013)

You would have to go the bespoke route. New spec -5 are an improvement and seem to spool up a few hundred rpm earlier. Add to that a agressive profile billet wheel and improve that further.


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## peckhs (Jul 20, 2013)

FRRACER, 

i was doing some more looking, and it seems that garrett's newer turbos has the GTX prefix.
Is there a GTX model that is similar to the GT2860RS?

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## EF Ian (Jan 11, 2013)

RBnutz said:


> I'm sure there is. But its in the form of a single. Companys don't bother with these little twins anymore.... apart from the said HKS, which are old tech.


Unfortunately I can't see a single coming on as smoothly as my GT-SS, which means I'd be more likely to break traction in my 260Z.

Might give a small single a go in a year or two if I get bored, and try and to control the power curve with some clever ECU settings.


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## GTR John B (Mar 9, 2014)

GTRNICK said:


> No but I do have set for sale with hks turbo elbows. I bought the car with them.running 1.4bar on high and 1 bar on low.
> 
> The car made 533whp at just under 1.4bar. So if pushed to 1.6 bar I reckon over 550whp.


I have some 2530's on mine pushing 554whp @ 1.6 bar.


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## FRRACER (Jun 23, 2013)

peckhs said:


> FRRACER,
> 
> i was doing some more looking, and it seems that garrett's newer turbos has the GTX prefix.
> Is there a GTX model that is similar to the GT2860RS?
> ...


No. They have updated the GT2860 turbos internally with ceramic ball bearings and metal cages. They are not GTX.


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## johnny_0 (Dec 12, 2003)

Just received the issue 12 of option mag.. next year will be release the all new hks t51 GT III capable of 1000/1100ps


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## joshuaho96 (Jul 14, 2016)

I've been searching for a while now but I still don't have clear answers on some questions regarding some of these turbos. I'd appreciate any guidance here:

1. For bolt-on, low mount twin turbos with a max potential crank HP of ~450-500HP, is the Garrett -7 or -9 best for the power target? Which would spool the fastest?

2. Does anyone know what the new -7 and -9 model numbers are with SiN/ceramic ball bearings? Some Google suggests that the -9 with ceramic ball bearings is 836026-2 but only for one german turbo site.


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## Zenki33 (Apr 6, 2014)

joshuaho96 said:


> I've been searching for a while now but I still don't have clear answers on some questions regarding some of these turbos. I'd appreciate any guidance here:
> 
> 1. For bolt-on, low mount twin turbos with a max potential crank HP of ~450-500HP, is the Garrett -7 or -9 best for the power target? Which would spool the fastest?
> 
> 2. Does anyone know what the new -7 and -9 model numbers are with SiN/ceramic ball bearings? Some Google suggests that the -9 with ceramic ball bearings is 836026-2 but only for one german turbo site.


If you mean CRANK HP figures, then I believe the -7's are up to the task with best response. I have -9's and feels about the same (stock engine) in terms of spool to the stock ceramic turbos, yet I made 480awhp on stock ECU/ENGINE but boosting 22 PSI and free flow exhaust system (3" NISMO/TOMEI no CAT)


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## Supertec (Jun 5, 2014)

Sold a set of -9 a few weeks ago. They are 836026-5002S/ GT2859R


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## joshuaho96 (Jul 14, 2016)

Zenki33 said:


> If you mean CRANK HP figures, then I believe the -7's are up to the task with best response. I have -9's and feels about the same (stock engine) in terms of spool to the stock ceramic turbos, yet I made 480awhp on stock ECU/ENGINE but boosting 22 PSI and free flow exhaust system (3" NISMO/TOMEI no CAT)


Is there any harm in running less boost through a -9 as far as response goes? It looks like the -7 is cutting it close and looking at the actual spec of the two turbos they seem more similar than alike.



Supertec said:


> Sold a set of -9 a few weeks ago. They are 836026-5002S/ GT2859R


Thank you.


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## RBnutz (May 7, 2012)

joshuaho96 said:


> I've been searching for a while now but I still don't have clear answers on some questions regarding some of these turbos. I'd appreciate any guidance here:
> 
> 1. For bolt-on, low mount twin turbos with a max potential crank HP of ~450-500HP, is the Garrett -7 or -9 best for the power target? Which would spool the fastest?


I'd also like to know the answer to this question. From what I can tell they are so similar that there really isn't much of a difference hence why there aren't any results and it almost comes down to personal preference or price. 

One thing I have noted is the adjustable garrett actuators that come with the -7 and others are ever so slightly smaller than the HKS branded ones. Assume this means the HKS units will be stronger and hold boost that little be better. 

I will probably buy a set of -7 for my car since they were original N1 equipment, but might also buy a set of 2nd hand -9 to compare back to back. Although this will be some years down the line.


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## Supertec (Jun 5, 2014)

Stock actuators have a weaker springs compared to HKS items. On the dyno found them not able to hold much more than 1.35. HKS has gone well up to 1.7 bar so far.


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## johnny_0 (Dec 12, 2003)

The new HKS T51 SPL in GTIII dress has been released

https://www.hks-power.co.jp/product_db/turbo/db/19370


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## Wouter (Jul 30, 2011)

^ Will be in stock end of next month in Europe. 

The GTIII-SS and GTIII-RS are available for next day - 2 days delivery in Europe. 

Just for info


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## johnny_0 (Dec 12, 2003)

From the Option magazine issue 8. The new T04z (4R)and T51 SPL (5R) turbo with Mitsu core and not Garett.


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## joshuaho96 (Jul 14, 2016)

To do a major thread bump, I actually ended up buying the HKS GTIII-SS turbos after a lot of hemming and hawwing. Multiple people have said it's actually a substantially smaller turbo than the -9s, hence why it makes less power. More comparable to -7s if anything, but with more modern compressor/turbine design for much faster spool.


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## kenecchi (Dec 7, 2014)

Maybe this has already been said somewhere and I've overlooked it, but AFAIK the -9, -7, etc. are Garrett GT series-based ball bearing turbos and the GTIII are Mitsubishi journal bearing turbos, so they're not really directly comparable. I'm sure they work well just the same as the inducer/compressor wheels probably have better aerodynamics than the old ones but I've heard they're not quite as durable.


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## joshuaho96 (Jul 14, 2016)

kenecchi said:


> Maybe this has already been said somewhere and I've overlooked it, but AFAIK the -9, -7, etc. are Garrett GT series-based ball bearing turbos and the GTIII are Mitsubishi journal bearing turbos, so they're not really directly comparable. I'm sure they work well just the same as the inducer/compressor wheels probably have better aerodynamics than the old ones but I've heard they're not quite as durable.


Not sure this makes sense to me, why would they be less durable?

The GTIII-SS really interested me because of this dyno chart, done by a US-based tuner:










But their tuning methodology may be different, I see them getting pretty crazy results from twin turbos compared to singles.


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## Lestat2369 (Sep 28, 2006)

I have them going on mine this month..excited ..but Im coming form stock everything..just the pill removal


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## joshuaho96 (Jul 14, 2016)

Lestat2369 said:


> I have them going on mine this month..excited ..but Im coming form stock everything..just the pill removal


Based on the dyno charts I've seen they won't respond as quickly as the stock turbo, but respond well to VCAM.


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## JOutterbridge (Nov 6, 2018)

Not an RB but pretty solid on pump gas and then E85. HKS GT III RS 3.4L 2JZ. They don't look like they run out of turbine as mentioned in a previous post at 700hp.


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## [email protected] M/S (Feb 16, 2002)

The turbo's make good power on a 2.8 RB with Vcam , making 600+ bhp at 1.2/1.3 bar boost


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## matty32 (Dec 18, 2005)

Good turbos, they came out just as i had the TOMEI fitted in japan, i wont change them now, as i cant have the v cam mapped without changing the midori ecu, but what i would go for i was building again


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## joshuaho96 (Jul 14, 2016)

JOutterbridge said:


> Not an RB but pretty solid on pump gas and then E85. HKS GT III RS 3.4L 2JZ. They don't look like they run out of turbine as mentioned in a previous post at 700hp.


GTIII-RS is a much bigger turbo compared to GTIII-SS, in the RB26 application the exhaust a/r of the GTIII-SS is 0.54 which is just a tad bit larger than the stock 0.49, the -7s and -9s are 0.64.


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## RB28 (Jan 14, 2018)

[email protected] M/S said:


> The turbo's make good power on a 2.8 RB with Vcam , making 600+ bhp at 1.2/1.3 bar boost


Have you got any more info? I've been considering upgrading my -5's on my RB28 Vcam setup


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## Zobo (7 mo ago)

What do you mean by "what i would go for i was building again"?


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## joshuaho96 (Jul 14, 2016)

Zobo said:


> What do you mean by "what i would go for i was building again"?


Presumably matty32 would've bought either HKS GTIII-SS or GTIII-2530 if given the choice to pick a set of bolt-on twin turbos again, rather than Tomei M8260. The ARMS M7655 and M8260 are known to be rather laggy for the power they produce.


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## matty32 (Dec 18, 2005)

At the time of pulling it together (original time scale) and ordering , the only Japanese twin set up available was the tomei. Or used 2530. I wanted all new. When the car was 90% done HKS then came out with the GT3s. Tbh it was another 2-3k I didn’t want to spend when I had brand new tomei items fitted. So the headache & cost of engine out , refitting etc Midori did say they would have preferred to use the HKS items but the 32 runs great. Yes a little laggy but I’m not out to set any time records.

if I had the choice upon the original order. Definitely the HKS ones.

am I going to go through that situation again … no but if you have the choice I’d suggest you go HKS


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## Zobo (7 mo ago)

Oh I see. Too deep into it to go back to HKS. Not a cheap hobby by any stretch.

I should be receiving my GTIII-SS soon from RHDJapan. Yen is really cheap to the dollar. Will be going in the next month on my built R32 GTR. Was also thinking step 1 vcam, but lead time is 210 days! Really like the response upgarageusa seems to get with that setup. I am really after 400 whp with early 350ish wtq - say 3500ish RPM. 

For the time being, what can I expect from these realistically without vcam? I have a lot done. To mention a few...
Link g4+
Japan Tomei B pon cams 260
R35 coils
Cam crank trigger
ID 1050 injectors
Twin 460 lph pumps and lines
Flex fuel
9:1 forged 2.6 L
No adjustable cam gears though

My biggest concern is the larger cams for these small turbos, especially hampering early responsiveness. Any suggestions and or data?

Thanks


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## Zobo (7 mo ago)

BTW...it's a long story...I will use the HKS turbos to break in my engine, and depending on the outcome, I may immediately sell them. 

My original intent was to go g30-660. Now the artec single cast mani is available for the RB26, so I may go that route with my set up. If so, I will offer the HKS twins for sale with very little kms.


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## joshuaho96 (Jul 14, 2016)

Zobo said:


> Oh I see. Too deep into it to go back to HKS. Not a cheap hobby by any stretch.
> 
> I should be receiving my GTIII-SS soon from RHDJapan. Yen is really cheap to the dollar. Will be going in the next month on my built R32 GTR. Was also thinking step 1 vcam, but lead time is 210 days! Really like the response upgarageusa seems to get with that setup. I am really after 400 whp with early 350ish wtq - say 3500ish RPM.
> 
> ...


I did a 4th gear pull, 2000 rpm in real world conditions. With no VCAM the GTIII-SS will get you 7 psi by 3000 RPM with purely wastegate spring pressure. This is with an untuned RB26, just the turbos swapped and otherwise stock. This is nearly identical to what UP Garage reports with their stock untuned R32 GTR dyno charts. Eventually I plan to get it tuned with VCAM but there's a lot of things that I still need to get figured out first. The Poncams will likely not affect spool as much as you'd expect as their centerline and thus valve timing is going to be different from stock even without cam gears.

The Artec manifold looks good but to me it's disappointing that it's not a twin scroll manifold. The whole reason why the RB26 was twin turbo in the 90s was that by having two parallel turbos there was better exhaust scavenging. This way there's no two cylinders that have overlapping exhaust events trying to compete with each other for exhaust flow capacity. One of the major benefits of a modern single turbo is that they can achieve this with a twin scroll design while retaining the practical benefits of reduced routing complexity compared to a twin turbo setup. When you look at BMW turbo I6s they either use a twin scroll single turbo or parallel twin turbo for gasoline.


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## Zobo (7 mo ago)

Thanks for the feedback. Maybe there is not much exhaust efficiency drop in these compact turbos with turbines smaller than 1. a/r. There must be a reason why Garrett only offers the divided t4 above that. Strange they only show 1.06 a/r divided option for the standard rotation and not reverse rotation on their catalog.

Who knows the intent for sure? Cost savings due to limited applications? Juice not worth the squeeze maybe?

I do like the stout shorter runners of the artec which will be less likely to crack while providing improved adiabatic efficient to the welded manis. Plus it appears to play nice with must have factory peripherals. Would be nice if it came with individual egt bungs but probably not necessary for 500 hp realm.

I will see how the flex fuel tune goes with the HKSs once installed. I like the factory twin look, and there is no doubt that it plays nice with the peripherals - ps, ac, and brake lines. After all, looking for a responsive 400 to 450 whp reliable street car. Just might work!

Ps...not sure what you meant in your last statement about the cam shaft timing differences bw stock and the pons and how it won't have impact on response.


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## joshuaho96 (Jul 14, 2016)

Zobo said:


> Thanks for the feedback. Maybe there is not much exhaust efficiency drop in these compact turbos with turbines smaller than 1. a/r. There must be a reason why Garrett only offers the divided t4 above that. Strange they only show 1.06 a/r divided option for the standard rotation and not reverse rotation on their catalog.
> 
> Who knows the intent for sure? Cost savings due to limited applications? Juice not worth the squeeze maybe?
> 
> I do like the stout shorter runners of the artec which will be less likely to crack while providing improved adiabatic efficient to the welded manis. Plus it appears to play nice with must have factory peripherals. Would be nice if it came with individual egt bungs but probably not necessary for 500 hp realm.


The intent is likely that the twin scroll is more restrictive with the same a/r due to the divider and smaller runners. However, the improved driving efficiency with twin scroll usually outweighs this effect. I agree that a low mount manifold makes more sense to improve time to g and provides less leverage for warping to occur in addition to making room for accessories. Generally speaking the twin turbos will have a smaller a/r than an equivalent power output single turbo. So a 1.06 a/r may not be as bad as it sounds. I would look at the turbine chart of a 2860R and double the flow rate to get an idea for what that looks like vs an equivalent single.



Zobo said:


> I will see how the flex fuel tune goes with the HKSs once installed. I like the factory twin look, and there is no doubt that it plays nice with the peripherals - ps, ac, and brake lines. After all, looking for a responsive 400 to 450 whp reliable street car. Just might work!


Shouldn't be awful, at least if your expectations are basically somewhere in the region of what the Garrett GT2560R/-7s, R34 N1, Nismo R1/R3 turbos will deliver. I think the general poor perception of these turbos in the US/Australia are mostly driven by two metrics. First is price, which HKS has never been great at competing in and just the nature of two turbos vs one means this was never going to be a battle that they could win. The second is power output. The GTIII-SS is not a big turbo, it's not really designed for huge power. 5652 55T means the compressor is substantially smaller than even the GT2560R in both inducer and exducer. The turbine is not quite as different but it is still a little smaller than the -7s.



Zobo said:


> Ps...not sure what you meant in your last statement about the cam shaft timing differences bw stock and the pons and how it won't have impact on response.


Factory R32 RB26 camshaft intake and exhaust timing is 113 degrees ATDC on the intake and 125 degrees BTDC on the exhaust. Genuine Tomei JP 260 type B poncams move this to 110 on the intake and 115 on the exhaust. So that represents 3 degrees of advance on the intake cam, then 10 degrees of retard on the exhaust effectively. This decreases the lobe separation angle and allows for more scavenging effects, just not as far as you can push things with VCAM. I suspect what UP Garage has figured out is that with enough intake VVT advance they can have significant amounts of air that doesn't even fill the cylinder and starts spooling the turbo directly instead. This is how modern GDI turbo engines put out monstrous amounts of torque as low as 1500 RPM. The reason why OEMs didn't do this in the port injection days is that doing this causes a bunch of fuel to bypass the cylinder entirely which is problematic for emissions and/or the catalytic converter. With GDI you can delay fuel injection until both intake and exhaust valves have closed so no fuel shoot-through occurs:











https://www.energy.gov/sites/prod/files/2014/03/f8/deer09_kirwan.pdf


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