Garrett G Series

[sneakey pete]

Gut feeling is that these would be a bit big for twins... At least for a direct comparison to -5's. More like enhanced -10s

[Birds]

I feared that might be the case. Though Garrett say suits 1.4-3 litre engines...assuming they're not talking about Group B rally cars lol...scaling that up, a pair of G25s in lightest trim could be good for a 26/30?

[Mick_o]

16 minutes ago, Birds said:

I feared that might be the case. Though Garrett say suits 1.4-3 litre engines...assuming they're not talking about Group B rally cars lol...scaling that up, a pair of G25s in lightest trim could be good for a 26/30?

Are you willing to go balls deep with custom manifolds, head work and piping etc Birdy?

Even then still realize you are talking about a potential 1100hp setup so its going to be laggy lol

[sneakey pete]

I actually had in my mind the sizes of the larger one (660) as the size of the smaller. Still, the 550 is the same size compressor/turbine as the -5, so barring the slight reduction in inertia from the webbing of the turbine disc being removed lag would be similar. Airflow would be greater but this could prove a challange to manage with restricted pipework etc.

Now, if the release a G20-440 or something like that.. that has -5 flow in a smaller size... that'll be a good candidate.

[Birds]

-5 lag on RB30 I can definitely deal with, particularly if it's going to be punching well above its weight. It's not unbearable on a 26. That would fill the middle ground that make people want -10s but scared off by the lag.

[sneakey pete]

Yes but i'm not convinced it would be worth it in terms of effort to make it fit and power compromises that would probably be involved.

[LaurelPWR]

Anyone taken the plunge yet?

[Mick_o]

I have a mate whos bought a G25 its going on a basic VE SR20 build. But its a while off yet sadly. ?

[Mick_o]

Also heard rumours of a GTR using twin G25s coming up soon ?

[LaurelPWR]

Anyone heard of any results anywhere yet?
Finding it strange that there's hype but no results on any forums..

[blah_blah]

Yeah have also been waiting on results but not seen any...

[r32-25t]

I think with them being t2 sized the main thing you’re going to see them on will be 4 cylinder engines

[discopotato03]

Well that's subjective really . If these things flow in the real world as well as Garrets claims then they could turn up on all sorts of things . Note the clockwise and reverse variants which you'd think were aimed at TT V bank engines .

 

[LaurelPWR]

Yeah for sure Disco..

 

There's already plenty of turbos in that size range that we run on our RB's... things like 2510, 2530, 2860, 2867, 2871 etc etc etc... yes they chock a little but they all perform well on low level RB engines.

 

As Disco said^ if these things flow the numbers Garrett are claiming, they'll be in the billet 3076 range on an rb25..

 

 

[Mick_o]

1st results in I've seen/heard of ?

[LaurelPWR]

1st results in I've seen/heard of [emoji106]  

 

  Just read the comments, it's the G-25 550 on a forged 2L engine on 99ron and using the .72 a/r rear housing.

This is looking very promising. Imaging what the G-25 660 on an RB25 with the same or next size up housing might be able to achieve and than add e85 to the equation [emoji848]

We might see GTX3076 high boost type power with response like a HKS Gt-Rs...

Here's the Facebook link -

 

EDIT: f**k....just noticed it's in flywheel HP [emoji17]

 

[fatz]

And seppo land to that’s more like 200hp

[LaurelPWR]

Yeh.... my excitement has been extinguished [emoji17]

[discopotato03]

Interesting - thanks for that .

I think we can safely say that either of these G25s could do a lot better than a GTRS on an RB25 particularly in the upper turbine housing sizes . The $64 question is what happens to turbo response with big housings on G25s .

I know its early days but the T25 or V band mount option is going to be a deal breaker for some . At least EFR offers a T3 mount plus integral waste gate on their B2 (I think it is) frame  turbos . I did search to see what was available in 3" V band to T3 adapters - but they won't be a compact arrangement . Having stainless steel means at least fabricating changes is a bit easier .

Given the release time on the G series Garrett is taking a long time to get them out there - and even longer to release info on the slightly larger versions supposedly in the pipe . I'm hanging out to see what the next turbine size up is capable of - and I'm guessing it won't have to be very much larger to be just what many roadies want for a street RB25 . EFR chose 58mm for their medium sized B1 units , if Garrett does something similar then they should be able to achieve GT30-GT35 type performance with hopefully better turbo response than either of these .

Time will tell .

A . 

[Lithium]

I feel like I'm missing something, why are you guys implying this is a disappointing result?  I doubt that's on kill, it's not on E85 and it's not given anything away to the GTX3071R (which is a very proven performer on RB25s) but picked a lot up in spool - despite using the bigger housing, which would be more suited to the 660 compressor on a 2litre.

Where has it gone wrong?

Edited March 4, 2018 by Lithium