Dyno Results for HKS GT III - SS Sports Turbo - Twins

[joshuaho96]

On 2/18/2024 at 12:32 PM, Lithium said:

Tbf impressive numbers in stock location (even if clearly huge work has been done to replace EVERYTHING about the stock mount setup) but it "sounded" pretty damn laggy and when I tried to keep an eye on the tacho to get an impression of when it started lighting up I realised the tacho is not working 🤔

They said it's running 4.11 diffs, so assuming this was dyno'd in 5th gear this is the power curve vs rpm (in white)

Not convinced this is better delivery than a 6870 like Hawkins asserted, even if it does look like there may be a bit of effort to deliver a softer boost curve it still is clearly quite laggy

The Tomei ARMS turbos they started worth have never been great. The M7655 is terrible for lag compared to -7s or the GTIII-SS.

[Predator1]

On the topic of the HKS GT III Turbo's....

What about GT75115_BB?

https://www.hks-power.co.jp/en/product/turbo/universal/index.html

Ive been having a look at this to replace my EFR9180 with. Theres a few cars that made 1250+hp with this on racegas:

https://www.hks-power.co.jp/product/turbo/universal/example.html

Anyone run this yet?? Especially on a 3.0 or 3.2 Perhaps?? Super interested..

[Lithium]

19 hours ago, Predator1 said:

On the topic of the HKS GT III Turbo's....

What about GT75115_BB?

https://www.hks-power.co.jp/en/product/turbo/universal/index.html

Ive been having a look at this to replace my EFR9180 with. Theres a few cars that made 1250+hp with this on racegas:

https://www.hks-power.co.jp/product/turbo/universal/example.html

Anyone run this yet?? Especially on a 3.0 or 3.2 Perhaps?? Super interested..

Look for results on Garrett G42-1450s, basically the same thing.

What is your target power etc?  Are you less worried about response now?

Edited March 25 by Lithium

[Predator1]

2 hours ago, Lithium said:

Look for results on Garrett G42-1450s, basically the same thing.

What is your target power etc?  Are you less worried about response now?

I am still after response, but I want to see what kind of a hit it will take.. I want to take my car over to Japan soon.

[joshuaho96]

22 hours ago, Predator1 said:

On the topic of the HKS GT III Turbo's....

What about GT75115_BB?

https://www.hks-power.co.jp/en/product/turbo/universal/index.html

Ive been having a look at this to replace my EFR9180 with. Theres a few cars that made 1250+hp with this on racegas:

https://www.hks-power.co.jp/product/turbo/universal/example.html

Anyone run this yet?? Especially on a 3.0 or 3.2 Perhaps?? Super interested..

Isn't that a slightly modified rebranded G42-1450? The GTIII-SS as far as I can tell really is an MHI TD04HL somehow adapted to fit a compact 5 bolt RB26 application.

[Lithium]

1 hour ago, Predator1 said:

I am still after response, but I want to see what kind of a hit it will take.. I want to take my car over to Japan soon.

That HKS turbo (or a G42 1450) would give a massive hit to response but definitely a heap more headroom too. I guess you just got to decide how much "heaps more power" or keeping some degree of down low punch matter though I think that's come up before.   Realistically expect the ability to make 800+kw @ wheels but also 1000+rpm more lag too. 

@DVS JEZ Ran a G42 1200 on his RB30 (so size down turbo from what you are asking about on the size down engine) and that even made big numbers, but also paints a picture of how much later spool will be.  Realistically probably not terrible for the power when you factor in the stroker, but if you're picturing something that drives like the 9180 then it's going to be pretty disappointing.

Edited March 26 by Lithium

[Predator1]

5 hours ago, Lithium said:

That HKS turbo (or a G42 1450) would give a massive hit to response but definitely a heap more headroom too. I guess you just got to decide how much "heaps more power" or keeping some degree of down low punch matter though I think that's come up before.   Realistically expect the ability to make 800+kw @ wheels but also 1000+rpm more lag too. 

@DVS JEZ Ran a G42 1200 on his RB30 (so size down turbo from what you are asking about on the size down engine) and that even made big numbers, but also paints a picture of how much later spool will be.  Realistically probably not terrible for the power when you factor in the stroker, but if you're picturing something that drives like the 9180 then it's going to be pretty disappointing.

Thanks lith. Wow thats hideous haha. under 150kw by 4 and 250 by 5. In comparison, I'm making 260 by 4, and 370 by 5.. and thats in 5th gear as well. From 4k the line is almost linear. Ive been looking at the 9280... Not sure if that will get me 4 digits either. 

I'm so addicted to the response that I dont really want to lose it.

Edited March 26 by Predator1

[r32-25t]

1000hp and response really don’t go together on these engines, it’s a one or the other kind of thing 

[Predator1]

39 minutes ago, r32-25t said:

1000hp and response really don’t go together on these engines, it’s a one or the other kind of thing 

Obviously. Trying to figure out how much of a hit it will have on my response.

[Lithium]

9 hours ago, Predator1 said:

Obviously. Trying to figure out how much of a hit it will have on my response.

I feel like you just need to soul search about how much what compromise matters to you.

Firstly, you're going to NEED ethanol for the kind of power you're talking about.

Next, how much does the absolute power figure matter to you?  There's a bit of a goldilocks type zone where you may not make 1000, or much over 1000hp but the car will be FAST and while not as punchy as the 9180, if you didn't think about or talk about the peak power figure then it's realistically (in my opinion) going to be a pretty epic all round road car.   I'm kindof thinking the Precision 6870/Xona Rotor XRE6869S area, maybe even the Xona XRE7169S.   They would both sacrifice some vs the 9180 but on the flipside they'll give you a reasonable step up in power while not quite fully committing to big turbo lag life. 

If you *really* want to walk past the 1000hp+ mark then realistically stop thinking too hard about the specifics of spool, its all going to be academic anyway.  You have a sequential, you have a big engine, its not going to be dead in the water like the old 2.6s would be at low rpm and once it's on "its on".   

The 72mm+ turbo combo on a 3.2 stroker is a pretty known quantity in terms of how usable they are, check out Andrew Hawkins driving videos with his G45 1450 on his RB32 GTR, or That Racing Channel when they put their Precision 7685 on their R32 GTR.  Ideally try and find someone with this kind of setup in real life as give or take - most 76mmish 1000+hp RB30 based builds are going to be "there or thereabouts".  Dyno plots aren't going to paint the picture anymore really at this point.

 

Edited March 26 by Lithium