Ford Focus ST Forum banner

1 - 20 of 29 Posts

·
Registered
Joined
·
613 Posts
Discussion Starter #1 (Edited)
New Garrett turbos released recently (not sure when, I just came across it today).

G25-550, 60mm compressor rated for 550hp
https://www.turbobygarrett.com/turbobygarrett/turbochargers/g-series-g25-550

G25-660, 67mm compressor rated for 660hp
https://www.turbobygarrett.com/turbobygarrett/turbochargers/g-series-g25-660

Compressor efficiency looks great too....very promising I think

Listed turbine size dimensions similar to GT28... if it can make the power claims while still being that responsive, that would be impressive.

 

·
Registered
Joined
·
1,274 Posts
Skepticism is fine. But I don't think it's worth worrying about if the output claims are legit.

Firstly, sigh the ST community really needs to understand something. When you deviate from the reference product all sorts of unintended things could happen. For ST owners the G series will solve a couple of problems.

1) It narrows selection down. Even if more product is on the way and it is, it's for mid-frame turbos that most of you aren't interested in anyway. Both turbos are similar in size to the GTX2860 and GTX2867.

2) Mid frame power in a small size. My GTX3071 is rated at 650 hp. Where I cannot get clarification is if that is at the wheels or at the crank. If it's at the crank, 578.5 hp (about 11% driveline loss) which is fine but if it's really 650 then that changes the fuel system requirements quite a bit.

Also with the smaller TB-04B compressor housing I get the smaller 3" inlet (outlets are the same) and I also don't get the additional benefit of the ported compressor housing. The G series eliminates that problem in a vehicle specific kit like the ATP I would enjoy all the benefits of the reference turbo.

This is why I put max flow of the GTX3071 at 550 hp at the wheels. Powned has already hit 480/420 at 26psi in the early stages of his tune. It should make 500 at 27-28 psi and 550 or so at 30-32 psi.

With the G series it's simple under <500 = G2-550 500> = G2-660

Where I don't like the GTX2867 is that it's slightly mismatched. If you have to give up 200-250 rpm of spool to get 25-50 hp I don't think that's a fair trade-off. Where the GS-660 spools likely the same way, you get a whooping helping of output.

Max output (if the hp ratings are at the crank)

550 = 489.5
660 = 587.4

Full Race and ATP both have these in-stock.

I've been told that for 2.0L .72 A/R is ideal, .49 A/R is for under 2.0L think Fiesta ST.
 

·
Registered
Joined
·
1,274 Posts
No kits yet.
 

·
Registered
Joined
·
1,274 Posts
JST Performance has kits and giving a free custom tune with them.
I did not see the G2 kits on their website.

These ATP kits will be much better based on the flow of the new turbine wheels (first in 20+ years from Garrett), especially since the .72 A/R turbine housing is standard which equals flow of the .86 GT25 housing that comes with the GTX kits.

.92 for rated power (minus driveline losses). One of the things I don't like about the GTX3071 G2 is the smaller 3" inlet and GT25 turbine housing, both limit ultimate output to the low 500's when the turbo is capable of near rated power of 600 with the reference turbo (T3 open turbine housing and 4" anti-surge inlet, with ported cover).
 

·
Registered
Joined
·
1,274 Posts
430 hp G2-550 S13 Silvia


Another SR20 Silvia 485 hp G2-660


ST should see similar numbers. I knew the 660 would give GTX3071 power in roughly the same package as my current ATP GTX3071 which uses smaller housings than the reference turbo.

As I said we are using the reference turbo in the ATP kits using the G2 series turbos, which means the rated power numbers are what they are.
 

·
Registered
Joined
·
15 Posts
More or less something like this (I used the same volumetric efficiency as on EFR graph above so you can compare):

Comp-Map-G25-550-lines.jpg
 

·
Registered
Joined
·
613 Posts
Discussion Starter #15
Get the G25.....for the sake of science lol. G25 compressor is very similar to 3071G2, more efficient event. The turbine side promises to make good power and keep spool up like a GT28 series would offer... in theory it's the best of both worlds. It's the latest tech and why it costs more.

I hate how a big turbo makes the low end lazy, so for me and a mid 500whp range target, G25-660 looks like a great option.
 

·
Premium Member
Joined
·
1,291 Posts
I was pretty sure that, short of a major failure event with my current gtx2867, I wasn't going to be purchasing another turbo kit anytime soon. The G25-550 turbo has me strongly reconsidering that. Anxious to see some real world ST impressions first though. Some of the initial hype makes me wonder if it's maybe a little too good to be true.
 

·
Registered
Joined
·
344 Posts
I was pretty sure that, short of a major failure event with my current gtx2867, I wasn't going to be purchasing another turbo kit anytime soon. The G25-550 turbo has me strongly reconsidering that. Anxious to see some real world ST impressions first though. Some of the initial hype makes me wonder if it's maybe a little too good to be true.
There are plenty of examples on other platforms. The turbo seems to be a bit better but all the higher HP G25-660 runs need the bigger 0.92 ar which means more lag, so nothing is for free I guess.
 

·
Registered
Joined
·
146 Posts
I got the 7163efr full race kit, im thinking about going g25 660 .92 ar tho for more efficiency and externally wg setup. Wonder how the two stack up.
 

·
Registered
Joined
·
40 Posts
Anyone have any practical experience with the g25-550 yet? I've been working with Rob at Edgeauto and he is strongly encouraging me to go with the g25 over the 2867r Gen 2 .64 or .86.

Also, going with the g25 means EWG. Just how loud is this setup? Can you still stealth around on no to low boost? Excuse the ignorance. This is my first turbo car.
 
1 - 20 of 29 Posts
Top