# Garrett GTX Gen2 thoughts



## brwmogazos (Oct 12, 2011)

The new Gen 2 GTX series turbochargers look rather nice with higher flowing compressors etc.

Looking at the "low" range Gen2s we have the GTX2867R which is still using the same 54mm turbine wheel but with a new compressor wheel which produces 550Hp!

Too shame they didnt combine this new compressor wheel with the 60mm turbine.

Has anyone tried one yet? A friend is already using the new GTX3076R Gen2 and compared to his old GTX3076R it spools 400-500rpm lower! and produces the same power at lower boost levels! That is on a forged audi S3 TFSi though.


Recently i bought myself a GTX3067R to upgrade my GT28RS but due to the load at work i was unable to have the new turbo-setup installed and those shiny Gen2s got me into thinking...

Keep the GTX3067R or sell it while its still sitting on my desk for a gen2 2867R?...


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## mainstayinc (Oct 4, 2006)

brwmogazos said:


> The new Gen 2 GTX series turbochargers look rather nice with higher flowing compressors etc.
> 
> Looking at the "low" range Gen2s we have the GTX2867R which is still using the same 54mm turbine wheel but with a new compressor wheel which produces 550Hp!
> 
> ...


Yeah. I was excited to see the second generation of GTX turbos when I was searching around the internet yesterday. The second generation GTX2867R (GTX2867R_2) looks exciting with an advertised 550 HP. However, when I looked at the compressor map, it only shows a maximum output of around 500 HP (see below).










I overlaid that with the first generation GTX2867R and they are not that different (see below).










The second generation GTX2867R is slightly better with an increase of about 25 HP in total output (500 v 475 HP). Also, the surge line is better, especially above P2/P2 = 2.5 (or about 22 psi) where it outperforms the first generation GTX2867R by 1000 RPMs on 1.8L displacement.

Consequently, you can expect better spoolup at higher boost pressures with the second generation GTX2867R and a modest 25 HP increase in overall output. Based on the compressor map, I cannot support the 550 HP advertised output for the second generation GTX2867R. Please note that other second generation turbos may be different.


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## brwmogazos (Oct 12, 2011)

I was looking forward to your reply tbh :thumbup: and for that compressor map comparison :wave:

Is that a plot of a 1.8l engine or your stroker?

Indeed the compressor map flow values dont seem to go along witht he advertised power figures.

Its nice to see the new surge line specs but i still dont understand why garrett didnt come up with a new Gen 2 3067R (60mm turbine wheel).

I cant say the 3067R etc was a "popular" turbo along with the GTX29 series so maybe thats why you dont see all those GTX GEN1 available in Garretts catalogue-range any more.

Looking at friends BT setups with upgraded internals, valvetrain etc the GTX2971R on stock displacement seemed to be limited at 2 bars of boost. The engine didnt produce more power at 2.2 bar so the power figures reached 500HP at the crank.
The same car had its internals upgraded once more (stroker kit) and again pushing more than 2 bars of boost showed no gains in performance.



Different car now with the GTX2867R Gen1 turbocharger seemed to have the same "symptoms". The turbo pushed 2.35 bar of boost and later on the owner upgraded the turbocharger with the GTX2871R where the max boost they pushed was 1.95 bar. It seemed as if the engine couldnt "breathe" and produce more power. The engine now has been upgraded to 2liters (stroker) and he will be installing the 3076R Gen2

So for both cars there seems to be a bottleneck arround ~ 500HP even thought they both have upgraded valvetrain and intake manifolds etc (no bottleneck there). (.63A/R is what both of these cars used on the turbine housing)

I believe the turbine wheel which is the 54mm NS111 if i am not mistaken for both these turbochargers, cannot flow enough so it becomes the bottleneck of the setup.


Based on the above i think even on my 1.8litre stock bore engine the Gen1 GTX3067R may still be a better match as i dont plan on using water meth and loads of boost to get the max out of it.

The improved spool on the GEN2 though...is something that affects my decision-plans (sell the 3067 for a gen2 or have it installed)


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## Vegeta Gti (Feb 13, 2003)

I won't buy into the bs again.only they big frame stuff(35r and bigger) seemed to truly see the task gains from the designs. Dozens of gtx turbos later, my buddy just had me deep his gtx3071 v1 to the v2...it still sucks vs my pagparts v1 bullet gt3071.

I do regardless like the gtx2867 as it had been a great turbo in several cars, crushing the gt version.


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## mainstayinc (Oct 4, 2006)

brwmogazos said:


> I was looking forward to your reply tbh :thumbup: and for that compressor map comparison :wave:
> 
> *Is that a plot of a 1.8l engine or your stroker?*
> 
> Indeed the compressor map flow values dont seem to go along witht he advertised power figures.


The plot is for stock 1.8L (1781cc) displacement.



brwmogazos said:


> Its nice to see the new surge line specs but i still dont understand why garrett didnt come up with a new Gen 2 3067R (60mm turbine wheel).
> 
> I cant say the 3067R etc was a "popular" turbo along with the GTX29 series so maybe thats why you dont see all those GTX GEN1 available in Garretts catalogue-range any more.
> 
> ...


I think the key to making power with the GTX turbos is better intercooling. GTX turbos make more power as compared to their GT equivalent due to faster compressor speeds. For example, if you look at the standard GT2860RS compressor map, the top compressor speed line reads 144,000 RPMs making about 360 HP (see below).










However, if you look at the GTX2860R map (see below), the top compressor speed line reads 185,000 RPMs making about 425 HP. That's more than 28% faster compressor speed than the GT equivalent which translates into 18% more horsepower (425 vs. 360 HP).









Faster compressor speeds means more heat at the compressor outlet. That additional heat needs to be cooled down to avoid engine knock and to maximize corrected air flow.


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## NaSMK4 (Dec 12, 2011)

I feel like these new gen 2's sound interesting but im still over here like... why is it so god damn hard to find information on the GTX2976R??? I can never find info on the newer turbos and it pisses me off nothing on youtube and google takes u to a lot of junk that is unrelated. when i say info i mean examples of people using these turbos its as if no one ever uses the newer turbos because the shops they go to recommend older turbos and then nobody ever gets the new technology... cant find any youtube videos of someone using the gtx2976r except for some guy in a full blown race car over seas and its in japanese from what i can tell and its just him driving the car no info of any kind u cant see the speedometer u cant see the rpm's u got no idea what kinda boost or power its making theres nothing..

I should mention i feel like the GTX2976R is almost perfect size power turbo we need for the 1.8t similar to the gtx3067r based on turbo maps but i could be mistaken if u can compare these turbos and give reasons why they might not be a good choice id be interested to listen currently sitting on a gt3071r with v2 billet blade from arnold but always looking to see if something else might be more fun.. currently making 398whp want to make anywhere between 450whp - 575whp.

Below is said video:
https://www.youtube.com/watch?v=oasLjUxzPZs

Oh apparently is a sr20det well it doesnt tell u much else tho.


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## mainstayinc (Oct 4, 2006)

NaSMK4 said:


> I feel like these new gen 2's sound interesting but im still over here like... *why is it so god damn hard to find information on the GTX2976R???* I can never find info on the newer turbos and it pisses me off nothing on youtube and google takes u to a lot of junk that is unrelated. when i say info i mean examples of people using these turbos its as if no one ever uses the newer turbos because the shops they go to recommend older turbos and then nobody ever gets the new technology... cant find any youtube videos of someone using the gtx2976r except for some guy in a full blown race car over seas and its in japanese from what i can tell and its just him driving the car no info of any kind u cant see the speedometer u cant see the rpm's u got no idea what kinda boost or power its making theres nothing..
> 
> I should mention i feel like the *GTX2976R is almost perfect size power turbo we need for the 1.8t similar to the gtx3067r* based on turbo maps but i could be mistaken if u can compare these turbos and give reasons why they might not be a good choice id be interested to listen currently sitting on a gt3071r with v2 billet blade from arnold but always looking to see if something else might be more fun.. currently making 398whp want to make anywhere between 450whp - 575whp.
> 
> ...


The GTX2976R is a big turbo capable of 650 HP on the right setup. For those power levels, I would recommend the EFR 7670 as that has a better surge line or the BW S200 or the BW S257 SXE. However, the smaller GT29 series turbine on the GTX2976R might improve spoolup as compared to the GT30/GT35 turbine. Not sure since there is no compressor map for this combination that I am aware of.

The GTX2863R or second generation GTX2860R is a great choice for a street car on stock displacement for overall power and spoolup. Below I overlaid the GTX2863R and GTX2860R_2 on stock displacement.










The second generation GTX2860R (BLUE above) is capable of 425 HP maximum output (about the same as the GTX2863R) but has a better surge line, especially above P2/P1 = 2 or about 14.5 psi. Consequently, you can expect better spoolup with the second generation GTX2860R as compared to the GTX2863R on stock displacement.

The GTX2976R and GTX3067R are totally different turbos in terms of surge line and maximum output. I probably posted something about these turbos in the compressor map thread.


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## brwmogazos (Oct 12, 2011)

mainstayinc said:


> The plot is for stock 1.8L (1781cc) displacement.
> 
> 
> 
> I think the key to making power with the GTX turbos is better intercooling. GTX turbos make more power as compared to their GT equivalent due to faster compressor speeds. .



I dont think those two specific cars i mentioned had issues with intercooling as the first one with the GTX2971R already had a large cooler and then had it upgraded with an ever bigger one (even thicker and more efficient core) and the second car with the GTX2867R -> GTX2871R was also running water meth and race gas. 

But still there seems to be a bottleneck somewhere arround ~500HP for both those cars. Both are using quality aftermarket parts, equal lenght exhaust manifolds 76-80mm exhausts, decat etc unless the .63 turbine housing A/R was responsible for this "bottleneck". I still think its down to the 54mm turbine wheel.


Its true that we havent seen much over the net from the newer GTX 29 and 28 series turbos. The gen2 2860RS might be the "best" street turbo for our engines as you get a bit of both worlds "spoolup and power up top". It looks very promising.

I am worried that the GTX3067R i bought might be a bit of a "lazy" turbo for my stock displacement, stock valvetrain setup. I really hope i can get some days off work to have it fitted and tuned so that i can see for myself how it performs.


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## mainstayinc (Oct 4, 2006)

brwmogazos said:


> I dont think those two specific cars i mentioned had issues with intercooling as the first one with the GTX2971R already had a large cooler and then had it upgraded with an ever bigger one (even thicker and more efficient core) and the second car with the GTX2867R -> GTX2871R was also running water meth and race gas.
> 
> But still there seems to be a bottleneck somewhere arround ~500HP for both those cars. Both are using quality aftermarket parts, equal lenght exhaust manifolds 76-80mm exhausts, decat etc unless the .63 turbine housing A/R was responsible for this "bottleneck". *I still think its down to the 54mm turbine wheel*.
> 
> ...


A lot of people around here would agree with you on the 54mm turbine wheel being a bottleneck.


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## G-zo (Oct 16, 2016)

From what I've seen on the Mazdaspeed forums, the GTX3076R spools the same if not quicker than the GTX2867R

I would get the GTX3076R over the GTX2867R.

But in general, the GTX line has been underwhelming from the start in terms of spool and power (at least Gen1).

We need an oversized NS111 wheel!


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## All_Euro (Jul 20, 2008)

G-zo said:


> From what I've seen on the Mazdaspeed forums, *the GTX3076R spools the same if not quicker than the GTX2867R*
> 
> I would get the GTX3076R over the GTX2867R.
> 
> ...



Not sure how that’s possible - all other things being equal. The GT 3076 is a bit of a laggy turbo for the 1.8T - I’d expect the GTX to be a little worse although more top end.


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## superkarl (Dec 18, 2012)

A rep commented that the gen 2 had revised turbine wheels. It was in reference to a picture of a 3582 on Instagram. 
He may have just been referring to that particular model, it's unclear


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## l88m22vette (Mar 2, 2006)

I've been excitedly waiting to use the GTX2863 I have sitting in a box but I've been hunting for a damn electrical issue and sideglancing at my TT for months. I am about to bite the bullet and get it towed/fixed before winter really hits, I'm ****in sick of just staring at it. I also rolled the dice and bought a Kinugawa .57 T3-to-vband turbine for the older Pag manifold, we'll see how that works out.


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## brwmogazos (Oct 12, 2011)

l88m22vette said:


> I've been excitedly waiting to use the GTX2863 I have sitting in a box but I've been hunting for a damn electrical issue and sideglancing at my TT for months. I am about to bite the bullet and get it towed/fixed before winter really hits, I'm ****in sick of just staring at it. I also rolled the dice and bought a Kinugawa .57 T3-to-vband turbine for the older Pag manifold, we'll see how that works out.


I am using the same PPT T3 manifold so i bought the Garrett .64 T3 to 3" V band turbine housing meaning i will have to modify or have a new downpipe fabricated to install my GTX3067R over the GT28RS (If i had bought the GTX2867R or today a GEN2 2867 then i could just use the same turbine housing as they have the same turbine wheel=less cost+time but i still believe the NS111 may be maxxed out with that compressor flow). Is that an adapter you are writing about? t3 to V band flange so that a vband inlet Turbine housing can be fitted?



The GTX2867R compared to the GTX3071R is a lot faster in spool so maybe the forum member that wrote the GTX3076R might spool faster than the GTX2867R actually meant the GTX3067R instead?

Can he paste a link on that mazdaforums thread?


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## brwmogazos (Oct 12, 2011)

That sounds interesting...

according to these two charts below the GTX3582 seems to have the same characteristics concerning the turbine wheel...design wise we couldnt know.

GTX

http://www.turbosbytm.com/download/Garrett_GTX_turbos.pdf


GTX Gen2

http://www.turbosbytm.com/download/Garrett_GTXG2_turbos.pdf

If those specs are valid then the new GTX2867R Gen2 most probably is using the same NS111 wheel which i believe is the case as Garrett has already combined the 71mm compressor wheel producing 560HP with the same NS111 wheel on the GTX2871R so i dont see why they would need to redesign the turbine wheel of a "revised turbo" that flows the same on the compressor side or even lower sinc ethe GTX2871R already exists in the product range 


Over the years we see new aerodynamics on the compressor wheels etc but no change in the turbine wheels...


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## mainstayinc (Oct 4, 2006)

brwmogazos said:


> I am using the same PPT T3 manifold so i bought the Garrett .64 T3 to 3" V band turbine housing meaning i will have to modify or have a new downpipe fabricated to install my GTX3067R over the GT28RS (If i had bought the GTX2867R or today a GEN2 2867 then i could just use the same turbine housing as they have the same turbine wheel=less cost+time but i still believe the NS111 may be maxxed out with that compressor flow). Is that an adapter you are writing about? t3 to V band flange so that a vband inlet Turbine housing can be fitted?
> 
> 
> 
> ...


That's what I was thinking. He probably meant the GTX3067R.



l88m22vette said:


> I've been excitedly waiting to use the GTX2863 I have sitting in a box but I've been hunting for a damn electrical issue and sideglancing at my TT for months. I am about to bite the bullet and get it towed/fixed before winter really hits, I'm ****in sick of just staring at it. I also rolled the dice and bought a Kinugawa .57 T3-to-vband turbine for the older Pag manifold, we'll see how that works out.


You are really going to like that turbo. Get that electrical issue solved!


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## mainstayinc (Oct 4, 2006)

I will be posting a comparison of the GTX3071R with the second generation GTX3071R later today. After an initial comparison, it looks like there is a significant improvement in the surge line for the second generation GTX3071R and some additional top end.


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## mainstayinc (Oct 4, 2006)

Below is the compressor map for the second generation GTX3071R.










I overlaid the first generation GTX3071R over the above map and highlighted areas below the surge line and above the choke line. The engine speed lines range from 1000 to 8000 RPMs and are for stock 1.8L displacement.










As you can see, the second generation GTX3071R is capable of 60 lbs. of air per minute (about 600 HP) at P2/P1=2.5 or about 22 psi at about 9000 RPMs on stock displacement. That's about a 30 HP increase over the first generation GTX3071R.

The surge lines (left side of map) are identical for each turbo up to about P2/P1=2 or about 14.5 psi. Above that point, the surge line for the second generation GTX3071R improves dramatically over the first generation. At P2/P1=3.0 or about 29 psi, the surge line for the second generation GTX3071R is 1450 RPMs lower than the first. 

Consequently, you can expect a significant improvement in spoolup with the second generation GTX3071R as compared to the first in this area of the map. Possibly as much as 1500 RPMs when boosting above 14.5 psi! Based on the compressor maps, it seems like Garrett may have addressed the major complaint people have with the first generation GTX3071R... that it is very laggy. I hope to see some real world testing to verify this conclusion.

Also, the efficiency range for the second generation GTX3071R increases by about 2000 RPMs between P2/P1=2.5 to 3.0 or about 22 to 29 psi. This means a wider power band for the second generation GTX3071R between 22 and 29 psi.


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## l88m22vette (Mar 2, 2006)

mainstayinc said:


> You are really going to like that turbo. Get that electrical issue solved!


Yep, that's going to be my Christmas present, might as well work on it during winter anyway. It'll be stock displacement unless I find a random deal on stroker stuff, but otherwise 9.5:1, SEM/AEB, 70mm, Fluidampr, maybe 350/325 to the wheels?



brwmogazos said:


> I am using the same PPT T3 manifold so i bought the Garrett .64 T3 to 3" V band turbine housing meaning i will have to modify or have a new downpipe fabricated to install my GTX3067R over the GT28RS (If i had bought the GTX2867R or today a GEN2 2867 then i could just use the same turbine housing as they have the same turbine wheel=less cost+time but i still believe the NS111 may be maxxed out with that compressor flow). Is that an adapter you are writing about? t3 to V band flange so that a vband inlet Turbine housing can be fitted?


This is an official picture of the housing, I meant to take pictures of my parts pile today but didn't get the time. The dink on the vband housing in the picture _isn't_ on mine, they used that housing for the pic since it was factory flaw (I asked before buying). I'm keeping an eye out for holiday sales, I basically need an in-take quattro setup, injectors, and the downpipe from Arnold. I'm thinking [email protected] for fueling for better atomization and more intake charge cooling on the higher compression..Is it stupid to think about a 5bar setup for my pretty modest build?


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## G-zo (Oct 16, 2016)

All_Euro said:


> Not sure how that’s possible - all other things being equal. The GT 3076 is a bit of a laggy turbo for the 1.8T - I’d expect the GTX to be a little worse although more top end.


Oops. I meant to say 3067 not 3076. The GTX3076R is pretty laggy


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## G-zo (Oct 16, 2016)

Focus


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## discopotato03 (Feb 17, 2013)

Hi all , I'm also interested in this new GTX3071R Gen 2 as a replacement for A GT3076R 52T (basically HKS GT3037 52T) .
I've also wondered why there isn't a Gen 2 GT3067R , I noted with this gen 1 unit it was the crossover point from T04B to T04E compressor housings ie 3067R to 3071R . 

Also yes please all keep harping on about the lack of a larger turbine than the GT28 NS111 76 trim one . Garrett does have , has for a LONG time , a 60mm version of that NS111 turbine in 73 and 76 trims . It's the basis of their TR30R series competition turbos and it may be made of Mar M material rather than the material most of the GT petrol turbos are made of . In fact I don't think the GT28 or GT30 rage of petrol turbos has seen any development since the early 1990s - yes early 1990s . 
They can't ignore the yawing gap between the GT28 and GT30 turbines forever and IMO no amount of mucking around with billet compressors is going to help this issue . 
What they HAVE done is developed a different turbine for the supposedly 1000 Hp capable GT3584RS - compared to the usual GT3582R's turbine . 
What I think they need to do is develop a 60mm turbine like the TR30R's NS111 with possibly less blades and a smaller hub than the GT30 has , probably in a smaller than 84 trim size too . 

Take care cheers DP03 .


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## mainstayinc (Oct 4, 2006)

G-zo said:


> Focus


Sorry, Gonzo. I totally missed your post. Thanks for the comparison. GTX3067R FTW!


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## mainstayinc (Oct 4, 2006)

discopotato03 said:


> Hi all , I'm also interested in this new GTX3071R Gen 2 as a replacement for A GT3076R 52T (basically HKS GT3037 52T) .
> I've also wondered why there isn't a Gen 2 GT3067R , I noted with this gen 1 unit it was the crossover point from T04B to T04E compressor housings ie 3067R to 3071R .
> 
> Also yes please all keep harping on about the lack of a larger turbine than the GT28 NS111 76 trim one . Garrett does have , has for a LONG time , a 60mm version of that NS111 turbine in 73 and 76 trims . It's the basis of their TR30R series competition turbos and it may be made of Mar M material rather than the material most of the GT petrol turbos are made of . In fact I don't think the GT28 or GT30 rage of petrol turbos has seen any development since the early 1990s - yes early 1990s .
> ...


Yes, I agree.


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## djfourmoney (Jan 7, 2007)

mainstayinc said:


> The plot is for stock 1.8L (1781cc) displacement.
> 
> 
> 
> ...


 I am going to bump this for a little more debate. I don't have a VDub but I have been a member of the forum since the mid 2000's, just a car enthusiast. 

My current car is a '16 Focus ST and it's having the engine internals upgraded now, should be back on the road in about two weeks so it's time to upgrade the stock turbo as well.

There is a bit of a debate over the value of the new Gen II GTX turbos. I agree with NYC, in-coming air must be cool, intercooling must be very good with little pressure loss; IE maximize the setup in order for these 28 series turbos to reach their max power ratings. 

I also think Garrett is adding E85 to their final max power ratings, even with high VE and knock resistant unleaded fuel; If the max rating of the GTX2867 Gen II is 500 but the turbo only flows max 47 lbs per min @61% efficiency, something is missing.

I've had long talks with both VP and Sunoco and the missing link beyond the efficiency of your setup is the fuel you run. 

Check out the The Tuning School's series on race fuel. They covered pretty much all of it, from racing concentrates to MS109 to C85 to C16. They also tried 50/50 (Boost Juice) and 100% M1 Methanol.

They used a Procharger boosted C7 Corvette with the stock pulley and upgraded exhaust = 574 hp on 93 octane.

638 hp with C-85 @40% and 100% M1 Methanol 
629 hp with C-85 @40%
Pump [email protected]% made 618 hp with better average hp and torque numbers than C-85

VP MS109 made 604 hp 
VP MS103 made 602 hp
Pump 93 with Boost Juice made 608 hp
Pump 93 with 100% M1 made 618 hp

I think it's pretty obvious what ideal here, but that depends on what's available to you.

This might answer that's going on here. I don't think Garrett or Borg Warner for that matter believe you'll hit those numbers on pump gas.

.2-.3 extra displacement especially if it's mostly a increase in stroke makes a BIG difference with the GT30-GT35 turbos, even the GTX29 turbos. The person who is building my engine built a 2.3L Ecoboost engine using the Mustang/Focus RS crank, Mazdaspeed3 Manley H beam rods and Manley Ecoboost/Duratec pistons. With a GTX2971 .86 A/R with EWG hit 20 psi by 3500 rpm and made 550 hp without a really aggressive timing map.

I also notice how EVO's when stroked to 2.3 can really use the huge turbos they tend to run to make 700 hp or more yeah still remain somewhat friendly on the street.


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## mainstayinc (Oct 4, 2006)

djfourmoney said:


> I am going to bump this for a little more debate. I don't have a VDub but I have been a member of the forum since the mid 2000's, just a car enthusiast.
> 
> My current car is a '16 Focus ST and it's having the engine internals upgraded now, should be back on the road in about two weeks so it's time to upgrade the stock turbo as well.
> 
> ...


I agree. There is clearly something missing here when one compares the compressor map and the horsepower rating Garrett assigns to their new Gen2 turbos. For example, I will be using the new GTX3584RS in my next project (MK1 Rabbit + 2.1L + E85). Garrett states that the turbo is capable of 1000 HP. 



atpturbo said:


> PRODUCT FEATURES:
> •Advanced aerodynamics Garrett GTX GEN2 billet aluminum compressor wheel
> •Ultra high flow "RS" blade profile turbine wheel
> •Dual ball bearing CHRA rotating assembly
> ...


However, if you look at the compressor map, the maximum corrected airflow (at 60% efficiency) corresponds to 90 lbs. of air per minutes. Typically on a 90 lb. per minute turbo, one would call it a "900 horsepower turbo". However, Garrett changed how it publishes horsepower ratings in the new Gen2 turbos. It's true, the GTX3584RS is capable of 1000 HP if you use E85 or Methanol.

Below is the compressor map for the GTX3584RS with 2.1L displacement (83mm bore x 95.5mm stroke = 2067 CC's). I marked two points, P1 and P2. P1 corresponds to 90 lbs. of air per minute at P2/P1 = 2.5 or about 22 psi. That is the maximum amount of air this turbo can flow at the choke line.










P2 corresponds to 84 lbs. of air per minute at P2/P1 = 3.3 or about 34 psi at 8700 RPMs. That is the point I am shooting for in my new project. Since I will be using E85, I plan to make just over 1000 HP (84 lbs. per minute x 12 = 1008 HP). So, yes, the GTX3584RS is capable of producing 1000 HP on the right setup with the right fuel.



djfourmoney said:


> This might answer that's going on here. I don't think Garrett or Borg Warner for that matter believe you'll hit those numbers on pump gas.
> 
> * .2-.3 extra displacement especially if it's mostly a increase in stroke makes a BIG difference with the GT30-GT35 turbos, even the GTX29 turbos.* The person who is building my engine built a 2.3L Ecoboost engine using the Mustang/Focus RS crank, Mazdaspeed3 Manley H beam rods and Manley Ecoboost/Duratec pistons. With a GTX2971 .86 A/R with EWG hit 20 psi by 3500 rpm and made 550 hp without a really aggressive timing map.
> 
> I also notice how EVO's when stroked to 2.3 can really use the huge turbos they tend to run to make 700 hp or more yeah still remain somewhat friendly on the street.


I completely agree with you that stroking a motor helps with spoolup versus just increasing displacement even on a GT28 frame turbo. I found that out on my MK4 daily driver (GTX2867R + 2.1L). Here is a thread that documents my findings. Basically increasing your stroke while maintaining the same size connecting rod reduces your connecting rod ratio. A shorter connecting rod ratio increases piston acceleration throughout your RPM range making the engine more volumetrically efficient. This thread discusses that issue a little further.

NOTE: I will have to re-host the images in this thread along with the other two threads I mention here since Photobucket will no longer host these without payment.


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