Garrett G-Series turbos
Originally Posted by MrLith
But I keep talking about comparing setups on the same displacement. OK, not apples and apples - but here's an RB26 (stock displacement, so smaller than the engine mentioned above) with a 72mm Holset turbo... it's well short on power but when you considering it is a journal bearing single turbo on a smaller engine...
They had their reasons, I guess. It has a sequential gearbox, spins to 10000rpm or so and to be balanced about it - while it is clearly laggy as all hell it IS exacerbated by the fact that they ease the boost in to try and stop it from being snappy/uncontrollable so that makes it look lazier in the 5500+rpm range than it probably really is. But that's a whole different topic, it's not how I'd do it but it is one of the quickest straight 6 powered cars around a race track in the world so can't be too bad. I am personally not a huge fan of twins on inline 6s.They really exaggerate any gains/drops in the curve because they crop anything outside of the mix/max readings on the graph. If the graph started at 0 it would look typical.At the start of a run, sure. Rolling road dynos can too.I agree with that, but again - this is what you and others told me I was wrong about. There are clearly differences in setups which maybe be blurring the comparisons we are making due to various variables but so far the short of it is I feel the typical result is the G25s spool like a size up from the turbo with equivalent wheel sizes on a GTX, and make power like two sizes up. There is NO way that a G3071 is going to be more responsive than a GTX3071R, which is again the point I was trying to drive home.
They had their reasons, I guess. It has a sequential gearbox, spins to 10000rpm or so and to be balanced about it - while it is clearly laggy as all hell it IS exacerbated by the fact that they ease the boost in to try and stop it from being snappy/uncontrollable so that makes it look lazier in the 5500+rpm range than it probably really is. But that's a whole different topic, it's not how I'd do it but it is one of the quickest straight 6 powered cars around a race track in the world so can't be too bad. I am personally not a huge fan of twins on inline 6s.They really exaggerate any gains/drops in the curve because they crop anything outside of the mix/max readings on the graph. If the graph started at 0 it would look typical.At the start of a run, sure. Rolling road dynos can too.I agree with that, but again - this is what you and others told me I was wrong about. There are clearly differences in setups which maybe be blurring the comparisons we are making due to various variables but so far the short of it is I feel the typical result is the G25s spool like a size up from the turbo with equivalent wheel sizes on a GTX, and make power like two sizes up. There is NO way that a G3071 is going to be more responsive than a GTX3071R, which is again the point I was trying to drive home.I'll have to drive one for a responsiveness comparison but for Zack to say it better than an FP Green on his autocross car has me sold that they work. Hopefully this car that's getting the g30-770 setup will be done by January for testing and results.
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Joined: Oct 2009
Posts: 41
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From: Medellin, Colombia
When i compared the g25-660 vband .72 ewg vs gtx3071 gen 2 vband .63 ewg is in the same car, same turbo manifold, same fuel, same dyno, same gear, etc.... I dont change the conditions, because i am interested to know what turbo is better for my car...
Evolved Member
Joined: Mar 2010
Posts: 715
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From: Welly NZ
I pointed that out to make sure everything is clear and fair - I am being neutral and basically pointed out something which if I was being disingenuous I would have kept quiet about it. I am not against the G-series, just managing people's expectations as if people expect the same spool as similar sized GTx- series then they are going to be disappointed. Anyway, I think I've made my point. I'd be happier if people took risks and tried the G-series, if I was wrong that would be awesome as I love the idea of something that spools better than a GTX3071R and makes power like a GT3582R, but it is not realistic.
To be clear, I'm not expecting 3582 power. I'm expecting spool, of around a 3071, but with a bit more power potential than a 3076.
The compressor map is pretty clear it's not an 800whp turbo.
The compressor map is pretty clear it's not an 800whp turbo.
Evolved Member
Joined: Mar 2010
Posts: 715
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From: Welly NZ
I'm not sure which turbo you are talking about, but where you started disagreeing with me was when the guy with the G3071 wanted better than GTX3071R spool from a turbo which touches 70lb/min, ie... comparable in flow to the OG GT3582R (very much NOT a 800whp turbo)
Evolved Member
Joined: Mar 2010
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From: Welly NZ
Someone with an RB25 powered Skyline did a back to back of a gen2 GTX3076R and G30-770 both running the .83a/r v-band exhaust housing options, but it was a stock internal RB25 on pump gas so they didn't really lean on it power wise. This is the resulting overlay, apparently on the same boost level (just under 20psi I believe)
Evolving Member
Joined: Dec 2012
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From: Mattawan, MI
Speed Academy on YouTube put a G25-660 on their 2.0L GR STi project and found the .72 turbine to be extremely restrictive, so they swapped to the .92 upon the recommendation of COBB tuning. I'd probably do the same for the above STi, but it might still be too small due to the higher displacement.
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Joined: Mar 2010
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From: Welly NZ
Yeah... The conclusions they draw from that "test" are bull****. First of all, that EJ has S1 cams in it, which are tiny, and not going to carry power out to the rpm they want anyway (and going to make the power curve look like it does). Secondly, they installed a new front mount intercooler in between dynos, which throws this "test" totally off. I'm pretty sure that's why the dyno of the .92 just destroys the .72 after it spools. Thirdly it's on pump gas, which is makes pushing the turbo impossible. It's pretty much routine to have to feed in boost on an EJ to have it make top end power. Lastly that dude from Cobb tuning seems kinda like he doesn't know what he's talking about. Recommending a 3584RS for a 450whp roadcourse car? WTF.
#noragrets
Newbie
Joined: Dec 2019
Posts: 1
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From: Dubai
G30 770 0.82ar on sti ej257 with pump gas and meth
Dyno result:
Dyno result:
- 470 whp & 466 ft-lbs @24 psi Pump Gas /Meth
- 565 whp & 570 ft-lbs @32 psi Pump Gas/Meth.
Last edited by Zuhair Yahya; Dec 22, 2019 at 10:36 AM.
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Joined: Jul 2013
Posts: 20
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From: New England
G35-900 Garrett Turbo on Subaru STi
G30 770 0.82ar on sti ej257 with pump gas and meth
https://youtu.be/Gow1C-9pEX4
Dyno result:
https://youtu.be/Gow1C-9pEX4
Dyno result:
- 470 whp & 466 ft-lbs @24 psi Pump Gas /Meth
- 565 whp & 570 ft-lbs @32 psi Pump Gas/Meth.
Dyno results:
500 whp & 454 ft-lbs @ 24psi Pump Gas/Meth.
603 whp & 546 ft-lbs @ 32.5 psi Pump Gas/Meth.
Newbie
Joined: Mar 2020
Posts: 3
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From: Dubai
Here's a G35-900
Dyno results:
500 whp & 454 ft-lbs @ 24psi Pump Gas/Meth.
603 whp & 546 ft-lbs @ 32.5 psi Pump Gas/Meth.
https://www.youtube.com/watch?v=igcdC-nXaCI
Dyno results:
500 whp & 454 ft-lbs @ 24psi Pump Gas/Meth.
603 whp & 546 ft-lbs @ 32.5 psi Pump Gas/Meth.
https://www.youtube.com/watch?v=igcdC-nXaCI
Also running an aquamist HFS-4 with 2 nozzles upstream of the throttle body (dont recall the injection rates).
According to the tuner (Sam Performance Dubai), with less restrictive headers, and an external wastegate dump, and race fuel, this setup is capable of 750 Whp
Here's a couple more videos:
Thread Starter
Joined: Sep 2006
Posts: 2,331
Likes: 39
From: Hermosa Beach, CA
This happens to be my ride. The highest octane pump gas available to us in the UAE is 98 RON (93 MON).
Also running an aquamist HFS-4 with 2 nozzles upstream of the throttle body (dont recall the injection rates).
According to the tuner (Sam Performance Dubai), with less restrictive headers, and an external wastegate dump, and race fuel, this setup is capable of 750 Whp
Also running an aquamist HFS-4 with 2 nozzles upstream of the throttle body (dont recall the injection rates).
According to the tuner (Sam Performance Dubai), with less restrictive headers, and an external wastegate dump, and race fuel, this setup is capable of 750 Whp
