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

[GTScotT]

6 minutes ago, djvoodoo said:

I was told to go a GTX3576R Gen2 on my 34 - Stock RB26 bottom end but with a refreshed head, baby HKS Cams, flex tune, usual mods. Have a 4 inch dump, 3.5inch exhaust running through 2 massive Reaper engineering mufflers. Very very quiet, until the wastegate and screamer come on song (which i love).

I couldn't be happier with the boost threshold, transient response and driveability. My goal was to try and compete with R35's for street duties (R35's are still quicker down low compared to my setup). 

Cant do much with my tune locked... But datalogging, doing a few pulls in 4th gear, last years winter, E85 and on flat highway loading the car up from 2400 rpm or so.

MAP sensor showing 155.8 kPA at 3569rpm -which by google translation is 22.5psi of boost. Pretty responsive if you ask me. Tuner said on the dyno was getting full boost (around 26-27 psi by 3800rpm)

 

I'd really love to get some seat time in such a setup as I'm struggling to find sufficient data for it online. Are you in Sydney?

[djvoodoo]

6 minutes ago, GTScotT said:

I'd really love to get some seat time in such a setup as I'm struggling to find sufficient data for it online. Are you in Sydney?

I'm in Sydney. Im sure we can try figure something out. I'll more than likely be at this years GTR festival and *may* do Motorkhana.

[joshuaho96]

5 hours ago, djvoodoo said:

I was told to go a GTX3576R Gen2 on my 34 - Stock RB26 bottom end but with a refreshed head, baby HKS Cams, flex tune, usual mods. Have a 4 inch dump, 3.5inch exhaust running through 2 massive Reaper engineering mufflers. Very very quiet, until the wastegate and screamer come on song (which i love).

I couldn't be happier with the boost threshold, transient response and driveability. My goal was to try and compete with R35's for street duties (R35's are still quicker down low compared to my setup). 

Cant do much with my tune locked... But datalogging, doing a few pulls in 4th gear, last years winter, E85 and on flat highway loading the car up from 2400 rpm or so.

MAP sensor showing 155.8 kPA at 3569rpm -which by google translation is 22.5psi of boost. Pretty responsive if you ask me. Tuner said on the dyno was getting full boost (around 26-27 psi by 3800rpm)

 

Curious to know what your dyno graph looks like vs this:

 

22 hours ago, GTScotT said:

I came across this thread looking for info on the GTIIISS and find myself reading another twin vs single debate.. 

 

If it means anything to anyone who still uses a forum.. I too watched the motive video of the 35R against the “-7s” and was sold. I then read the SAU gospel and witnessed the infamous “twins in the bin” meme. Unable to disobey the word of the lord our saviour, I installed the fabled 8374 at considerable cost and have unfortunately resigned to the fact that it’s not all it’s cracked up to be. 
 

The Motive video in question alludes to the fact that the -7s are high flowed but doesn’t give any specs. The car makes 500whp in the video, more than what -7s should make. It’s anyone’s guess what the specs are or how those twins actually perform.. Meaning the video could be showing that half ass twins aren’t as good as a 35R. Like much of the GR Yaris content from the same source.. A crock of shit. 
 

I’m running a bar of boost through my 8374, the car is fast.. But my friends almost identical GTR running a bar of boost through R34 twins is faster. More under the pedal, more when you want it, more over a wider spread. 
 

I’m certain if I threw another 40 grand at the car I could see the 500rwkw that would make the 8374 show how amazing it is compared to other 500rwkw turbos.. But it’s not the “better in every way” dream this forum and the internet at large portrays it to be. 
 

I find it really difficult to find information from Japan, but I have seen a lot of evidence that Japanese tuners are reverting back to twins and aiming for less power. This brings us to the GTIIISS… 

 

I am still legitimately interested to know if they would be better than -9s, and if so by how much? Another thing I am curious of is if a smaller single would keep the simplicity but give back the drive. Adam LZ did the video of the G30-770 on his VCT equipped RB, the graph shows it standing up at 4 and the driving scenes aren’t much different. Perhaps better than the bolt on 8374.. But not by much. 
 

Keen to discuss sub 350kw 98 only RB26. 

The GTIII-SS is not going to make more power than a GT-SS/-9s on the same engine. Nobody who knows the specs of these turbos would promise this. Not even HKS’ own marketing suggests this. It is a smaller turbo than the GT-SS both compressor and turbine. As far as I can tell the GTIII-SS is about as capable as the -7s for power potential but because it’s smaller I have seen dyno charts that suggest with VCAM it might be able to spool significantly faster than -7s as a result. If you push the -7s hard with E85 I would not be surprised if they’re capable of more power than the GTIII-SS as the turbine is larger and the housing is a larger a/r. I recommend poking through the UP Garage/Fairlady Motors Facebook page for their dyno charts. I don’t know if everything they put out is “real” but my own R33 with the GTIII-SS turbos running the stock tune and stock everything else with wastegate boost almost perfectly tracked their stock tune stock turbo dyno run for boost vs RPM in 4th gear.

It’s also worth mentioning these turbos are journal bearing which makes for a weird trade off between bearing drag and less rotating assembly inertia when comparing to stuff like the Nismo R3 and -7s.

My personal opinion is that for a street RB26 one of those 300 kW options with VCAM is probably the way to go. If you’re doing the build with the bottom end apart you can also cut valve relief into the pistons to run either VCAM step 2 or make your own step 1B by removing the limiter block on the cam phaser. Single turbo for 300 kW would be an interesting project if the manifold was low mount, twin scroll, designed for something like an EFR7163. It’s so much work though that it may be easier to just spend some hilarious number on the HKS complete intake kit they’re working on instead of going single turbo to improve the piping situation. 

[djvoodoo]

41 minutes ago, joshuaho96 said:

Curious to know what your dyno graph looks like vs this:

 

 

Pretty sure i've posted my graphs in the past on a thread about GTX3576 VS GTX3076 or something.

Note - Hub Dyno. So an approx conversion at say 1000 axle rpm speed x 1:1 gear ratio x 3.54 diff ratio (R34 Getrag) = 3540rpm or there abouts for 21+ psi of boost.

In the real world, im not sitting there staring at my boost gauge while driving, but i've had -9's in the past too, and i prefer the single.

[Dose Pipe Sutututu]

Not a like for like comparison with @djvoodoo, but here's my GTX3576R Gen 2 with T3 1.01 divided rear on a RB25 NEO, rev limiter set at 8600rpm. Housing is a bit large, but actually worked out well in the end as I wanted a wide powerband and flat-ish torque for the circuit. The only thing I would have liked was to fit smaller duration cams. At the time I ordered cams, Kelford said it would be a 2 month wait for the 264/264° cams so I ended up with 264/272°.

[Piggaz]

Considering Voodoo‘s results using a Gen2 3576, something along the lines of a Gen2 3071/G series 660/ EFR 7163 or something similar would be right up the alley for the goal here. Depending on how fancy your want to get, go all in with a TS manifold (not sure why if you’re doing the swap you wouldn’t go that extra step as you’re buying a manifold and rear housing to suit anyway).

Between buying and optimising all the junk needed for a twin setup… dumps, front pipes, playing with the twin turbo pipe, potentially AFM’s, hard pipe kit and the turbos themselves, going from a totally stock car to a single there wouldn’t be that much price difference. Couldn’t be assed sitting here and working it out.

An open scroll 3576 is doing it’s thing by high 3000’s on a stock donk, drop down a couple snail sizes to fall in line with what a typical -7/-9 setup would do and the result would take a big steamy turd of the twin buttplugs. The thing is guys don’t buy a turbo that’s the same flow rate as what the twin turds will flow, it’s always more.
 

 

[joshuaho96]

On 4/29/2023 at 4:03 AM, djvoodoo said:

Pretty sure i've posted my graphs in the past on a thread about GTX3576 VS GTX3076 or something.

Note - Hub Dyno. So an approx conversion at say 1000 axle rpm speed x 1:1 gear ratio x 3.54 diff ratio (R34 Getrag) = 3540rpm or there abouts for 21+ psi of boost.

In the real world, im not sitting there staring at my boost gauge while driving, but i've had -9's in the past too, and i prefer the single.

Genuinely not sure what's up with your results vs what people are getting here in the US. Regardless, I still think if the goal is just pure response on the street that the GTIII-SS is the most straightforward way of getting there. VCAM step 2 with those turbos supposedly can get you ~150 kW by 2000 RPM, at that point I would be more concerned about whether the bearings can take that much torque that soon with the stock oil pressure vs RPM curve. I don't doubt that an EFR7163 is theoretically capable of doing better but to actually realize that potential seems to be more effort than it's worth. Most manifolds aren't designed for the 0.8 a/r twin scroll housing, runners tend to be long to have equal length or place the turbo so you can fit an EFR9280 rather than focusing on reducing runner volume/length. Basically to run a relatively small turbo like that I'd want a manifold that looks more like this, obviously flipped to account for the hot side being on the LH side of the car rather than the RH side:

[GTSBoy]

Ick. 2J manifolds are awful.

But I know what you're saying. It's actually worth just building a nasty looking log type manifold with a little bit of added care and attention, to do something like a 7163. The factory manifold, with external WG added, can be used up to somewhat stupid power levels. Just doesn't have as much spunky noise.

[Piggaz]

GTII-SS is a glorified SS/-9 with lazy journal bearings.

It wouldn’t be hard to beat it. 

Stockers are average at best, lazy, laggy, soft as a sponge cake under foot and boring. Going bigger just makes the whole turd system worse.

Josh, so throw a vcam at a stock 2.6 with a budget gtx gen2 3071 (insert your flavour of snail brand) open scroll, let alone a TS setup. I would bet my own car that it would kick the shit out of a SS/-9/ whatever the latest shit offerings that HKS have on offer, out of the park.

 

 

[r32-25t]

1 hour ago, Piggaz said:

GTII-SS is a glorified SS/-9 with lazy journal bearings.

It wouldn’t be hard to beat it. 

Stockers are average at best, lazy, laggy, soft as a sponge cake under foot and boring. Going bigger just makes the whole turd system worse.

Josh, so throw a vcam at a stock 2.6 with a budget gtx gen2 3071 (insert your flavour of snail brand) open scroll, let alone a TS setup. I would bet my own car that it would kick the shit out of a SS/-9/ whatever the latest shit offerings that HKS have on offer, out of the park.

 

 

The GTIII-SS isn’t even big enough to match a -9, 

[anicenero86]

Finally dyno'd the GTR. Results as follows:

446rwhp (332rwkw) / 387ftlbs @ 18psi, 433rwhp/363ftlbs @ 17.4psi, 330rwhp @ wastegate pressure 12.4psi

all on 92 octane pump, decided not to push past 18psi. Fine with the Tomei manis impacting spool time. Really fun to drive.

Parts:

HPI 76mm dumps

HKS GTIII-SS turbos

Tomei cast manifolds

Bosch 950CC injectors

Radium 10mcrn filter

Aeromotive FPR

HPI 70-80mm front pipe

HKS 80mm cat

HKS super turbo exhaust

Haltech Plat Pro

Okada Projects coils

Haltech WB2 Bosch O2s

Tuned on Haltech MAP

Edited January 25 by anicenero86

[anicenero86]

On 3/9/2023 at 12:23 PM, joshuaho96 said:

400 kW sounds highly optimistic for the GTIII-SS considering it's a smaller turbo than the original GT-SS. The best I've seen from a Mustang dyno is something like 300 kW on the dot. I would personally be happy with something like an honest 280 kW to the wheels.

Josh, I'm on stock internals and landed 332kw atw on dynopacks. I also didn't expect to make anything over 300kw based on Midori dynopack results from Japan on 34s not netting anything higher than 380-410whp.

[Dose Pipe Sutututu]

120kW at 4000rpm would be really fun to drive.

[anicenero86]

17 minutes ago, Dose Pipe Sutututu said:

120kW at 4000rpm would be really fun to drive.

Tomei manifold impacted power curve. Next

[Dose Pipe Sutututu]

I'm not against twins, however to get them to work properly you need to take a page out of BMW's book.

Each turbo has its own exhaust path quite far down before the exhaust mixes at the rear muffler.

Each turbo has its own IC chamber before it all meets just before the throttle body.

Unfortunately, noone has properly done twins on a RB, realistically it's not cost effective.

[anicenero86]

4 minutes ago, Dose Pipe Sutututu said:

I'm not against twins, however to get them to work properly you need to take a page out of BMW's book.

Each turbo has its own exhaust path quite far down before the exhaust mixes at the rear muffler.

Each turbo has its own IC chamber before it all meets just before the throttle body.

Unfortunately, noone has properly done twins on a RB, realistically it's not cost effective.

The next time I remove these turbos, it will be to put a single on. That has nothing to do with performance, but because of simplicity when installing and maintaining. It is ridiculously time consuming to maintenance based on engineering design. I do believe both twins and single turbo set ups are fine. 

[GTSBoy]

1 hour ago, anicenero86 said:

The next time I remove these turbos, it will be to put a single on. That has nothing to do with performance, but because of simplicity when installing and maintaining. It is ridiculously time consuming to maintenance based on engineering design. I do believe both twins and single turbo set ups are fine. 

And, as a bonus, you'll get better performance. Win win.

[joshuaho96]

6 hours ago, Dose Pipe Sutututu said:

I'm not against twins, however to get them to work properly you need to take a page out of BMW's book.

Each turbo has its own exhaust path quite far down before the exhaust mixes at the rear muffler.

Each turbo has its own IC chamber before it all meets just before the throttle body.

Unfortunately, noone has properly done twins on a RB, realistically it's not cost effective.

HKS tried with the advanced heritage intake system, I'd be curious to see to what extent it resolves the problems in real world testing: https://www.hks-power.co.jp/en/product_db/intake/db/33150

The MSRP on that thing is obscene but that's just a price model thing, you could make most of it out of rubber, plastic, and maybe some cast aluminum to reduce the cost in a mass produced variant.

The other issue is the turbos are fighting each other for the same space basically. The S55/S58 manages to package twin turbos a lot better because one goes below the other. Still a bunch of pipe spaghetti but it's not like an RB where the front turbo dump is crammed up against the rear turbo compressor. The N54 put the two turbos butt to butt but that wasn't much better, it made the downpipes do a 90 degree turn basically right after leaving the turbine still.

I really need to get around to doing VCAM + various other modifications to my R33 but a lot of life has gotten in the way so I've left the car alone thus far. The GTIII-SS for now accomplishes the three main things I really want which is not being a 30 year old ceramic turbo threatening to destroy the engine at any moment, not shifting the power curve too substantially to higher RPM compared to other bolt-on twin turbo options, and not giving up any reliability relative to a totally stock car.

Is it possible to achieve OEM levels of reliability and driveability on an RB26 single turbo? Is it possible to make a single turbo setup optimized for passing CA emissions and to suit small twin scroll turbos that top out somewhere around 300 kW? The answer to those questions is almost certainly yes, I just don't have the time/money/knowledge to make all those things happen.

[morboost]

On 28/04/2023 at 9:49 PM, morboost said:

 

I think its reverting back to twins as consumers are looking more and more for slightly modded gtr's that they can do mods slowly and enjoy the tuner aspect, start off with a nice jdm twinturbo back exhaust, why would you want single when you just dropped 2-4k on jdm dump and front pipes, now you want to capitalise on your exhaust with some bolton twins to go with z32 mafs or hks deletes on the stock airbox with some sort on carbon nismo component. The car ends up looking fantastic under bonnet has good usable power doesn't sound like a vl turbo with and exhaust leak and is appreciated buy a large audience, and if life goes sideways you can sell the car quick.

 

where's that single in the bin meme.

my other car is a Delorean

[Lithium]

On 17/02/2024 at 11:50 PM, morboost said:

my other car is a Delorean

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