Lithium

I don't know anyone who have gone with the 1.05 and regretted not going smaller, I know plenty who have gone the other way though.

Which fuel? I tend to have a strong preference for the externally gated housings btw, the 1.05 would be fine on a 2.6 I reckon -especially if you are aiming for that kind of power area.

And that's exactly where I am at, if these are anything to go by - and the response matches what we'd expect from a Garrett with those wheel sizes, then a G30-range could be a game changer. They should be shipping from December/January apparently, here's hoping some people get their hands on them and let loose.

Nice - that's a solid result, cheers for posting How does it drive, real world?

Nice! What exhaust housing is that running ? 1.05 or 1.45? And is that pump gas ?

Yeah I was a bit surprised too, I am sure I saw hints somewhere they were toying with them but it looks like the gas hits the blade in a fairly radial manner going by the wheel shape on the G25. Otherwise yeah - 9 blade turbines seem to be a thing of the moment currently Either way, going by what they are saying they clearly flow really well - here is hoping they derive enough torque from the exhaust gas to drive the rotating mass good... They are suggesting that the new design also improves spool which is pretty epic if accurate for a given wheel size, especially with the massive flow improvement.

https://www.full-race.com/product-category/garrett-turbos/garrett-g-series-turbos/ Go here then

Sorry - no, poor wording. I actually know no one directly who has had a failure, I know guys who have been pushing 40psi through a 9180 without issue. There is just the stigma of overspeeding and the intolerance of the Ti-AL turbines to it, it apparently can happen but given the sheer amount of people running around with them now it doesn't seem THAT bad but it is still a thing which people are aware of. The most recent failure I know of which is third hand was a WRX which I if I remember rightly (bare in mind, this was "a guy who knows a guy") think was used for sprints which ran an EFR6758 and was running it on full on kill for a fair length of time, maybe 400whp or just over I think and eventually lost the turbine. That would have been pushed way harder than what most people would expect them to deliver - but it still lost the turbine, where as most people these days just expect to run out of flow. If they had a turbine speed sensor or generally kept it within the expected flow they likely wouldn't have had any issues, and even then it didn't fail immediately by any stretch. * Disclaimer, could be inaccuracies in this story but this is the way I heard it. I actually know someone who had something go through the engine on their EVO running an EFR8374 it went through the turbine wheel as well, something which me and other have discussed and speculated on what would happen if this occured - turned out the damage was no different at all to what I'd expect to see on an inconel wheel. There is a tiny and what you could almost consider to be "cosmetic" chip on one or two of the blades, far from the "explode" which had been speculated on in the past. Not sure of it's fate from here, and not sure if it'll stay being so happy - but apparently they aren't so fragile that something hitting them at speed means immediately explode.

Looks like Garrett have stolen the show this year, here's hoping the G-series deliver on the potential they look like they have. It'd be nice if there was something as good or better performing than the EFR range but without quite the price, packaging and reliability hurdles

The compressor and turbine maps will be taking those into account, given that they have different turbine flow maps for the different housings. The max wheel speeds are no greater than the old plastic bearing cage -5s which have been running around for ages, and they have definitely done development on toughening up the core construction on these - though even the GTX series (for interest, the Gen1 GTX2860R's max rpm is 185,000!!!) all had steel bearing cages etc. I doubt there will be an issue there, the rpm sound crazy but it's not unusual for smaller OD compressors to go even faster. I am really interested to see the real world performance, however. I'm not going to count any eggs before they are hatched - but if my arm was twisted behind my back and I were forced to say they're going to be good or not... I'd say they're looking pretty promising.

First time Garrett has released something which has given me a flicker of excitement in a long time, at least based on the information they've given so far and the clear effort that they've put in. Those maps look awesome, the work they've done on packaging and reliability is very promising, and the flow for the wheel sizes basically is insane. Mar-M doesn't seem any lighter for size than the EFR range but at a quick quick glance at the flow maps etc, if you were considering a turbo upgrade and EFR and Garrett turbos are options - you have all the data for these so you can actually compare. The G25 fits between an EFR7064 and an EFR7670, so I'll pick a point which is in between (really RB25s would like a turbo between those two sizes) so I'm going to compare a .92 EFR7670 and a .92 G25-660. With a mega-rushed attempt at working how well matched they'd be at 6500rpm on 20psi on a stock RB25 (I'm using ~51lb/min as a target) .92 TS EFR7670: Compressor inducer: 57mm Compressor exducer: 76mm Compressor efficiency: 67% Turbine wheel OD: 70mm Turbine inlet pressure: 3psi above boost pressure Turbine speed: 103,000rpm (74% of max) .92 open scroll G25-660 Compressor inducer: 54mm Compressor exducer: 67mm Compressor efficiency: 67% Turbine wheel OD: 54mm Turbine inlet pressure: 3psi above boost pressure Turbine speed: 137,000rpm (83% of max) So, the G25 is working slightly harder than the EFR to achieve what it's doing - however doesn't have a fragile Ti-AL turbine wheel to deal with, has a much smaller compressor and more importantly a WAY smaller turbine wheel... like way way smaller. It doesn't have the fancy light Ti-AL material the EFRs have, but moment-of-inertia has a huge amount to do with how much of the mass is how far from the rotational centre. I don't know how the materials compare weight wise but this turbo has a significantly smaller turbine wheel than ANYTHING in the EFR range, if they ended up weighing the same as the comparatively giant EFR7670 turbine wheel then they'd still have a much lower moment-of-inertia... which is where your response comes from. Going by the turbine flow map this doesn't mean you are going to choke your engine, in fact - at the hypothetical 20psi & 51lb/min point that I picked, the turbine flow is very comparable with the .92a/r EFR7670. The trick is there is much more to it than just the wheel sizes, it depends on how they've managed to get such huge flow from such small turbine and compressor wheels - they could be coming at some other cost but I am VERY interested to see the real world performance of these things. I wouldn't count out the possibility of these being something that put the BW EFR range on notice performance wise, but with better reliability than the previous Garretts - let alone having to worry about turbine overspeeding as a thing.

OK this all sounds a bit odd tbh. I am pretty sure Mat's 8374 is no laggier than that on his 2.5litre, and then there is of course this result from bri73y, the red line being an EFR7670 with 1.05a/r housing on pump gas, blue is his old HTA3076. With the EFR7064 we are seeing 1bar at around 3000rpm in 3rd on an RB25 with an open housing internal gate setup, I'd have expected a twin scroll EFR7670 to only be a few hundred rpm laggier.

We still haven't had a good dyno session with it thanks to boost control and ignition issues - I think we hit around 280kw @ hubs before ignition break down stopped our last session, however we've got it holding around 21psi on the road now and no misfire so hopefully when we next get on the dyno all will be well. It builds boost VERY similarly to an HKS GT2535, but with the EFR "transient response" and more turbine flow - so more power per psi, it's pretty good for a >50lb/min turbo.

Sweet - so yet to be confirmed, but probably not the turbo/setup itself so much as how the ECU boost control is setup then. Here's hoping that's the case, it'll be a lot cheaper/easier to resolve

Would have been good without the ECU boost control turned on so we know if we are dealing with a mechanical boost control problem. This makes it look a lot like a tuning issue - if I were tuning it the first thing I would be doing is getting a baseline with purely mechanical boost control to know with certainty where I should be looking. We could go around in circles with ECU setting discussions if it's mechanical, and alternately trying to work out what is going with the mechanical side of thing with data skewed by quite a lot of ECU influence makes the data hard to draw any meaning from

LOL! I have been trying to put my response together in fits and starts for the last hour or so, this is very much what I was thinking when I wrote mine two. Very much agree with this, I've been here done that myself.

Can you give as much detail as possible about what you've done, or link to a post to it? Ie, what brand exhaust manifold? What exhaust setup? How does the wastegate dump merge with the rest of the exhaust (if it does) What intercooler? Do you have pics of any of these things? What blow off valve? You have definitely tried this with the open loop boost control turned OFF completely? The stickler in me feels that so long as there is any electronic boost control influence involved, it could be to blame - not saying that I believe that's what it is, but it should be ruled out. Something that sticks out to me is I understand there are possibly two issues, 1) It seems laggier than expected 2) It boost spikes Some of the most common causes of #1: - Boost leak - Poorly performing exhaust (pre or post turbo) - Pre-turbo exhaust leak Some of the most common causes of #2: - Boost leak - Poorly performing exhaust - Waste-gate problem - Tuning (particularly where electronic boost control is involved) I don't have heaps of time to do more than just spit out the first things that come to mind, but it's hard to ignore that you have 2 weird issues which have 1 or 2 common causes - quite a coincidence.

@bri73y runs an EFR7670 on an R33 GTS25t (still RB25) on 98 and from all I can tell he is pretty happy with it's performance, he shared this dyno plot (EFR7670 vs HTA3076 on pump gas) showing the 7670 making near 370rwkw and 200kw by 4000rpm

Best reason I can think of. They are a bit cheaper but they are also relatively laggy for the power they make compared to more popular/big name options - in my experience

In context there are probably not many current alternatives which bolt on so easily and perform fairly well - though as soon as you go to custom piping etc I think you're better off looking at the likes of Garrett etc.

Not that I know of, however a lad I know is currently doing an EFR7670 with the .92a/r twin scroll hotside on a tubular twin scroll manifold on an RB26 with basic cam upgrade... was running N1 turbos previously.

What kind of dyno will your car be tuned on? Worthy heads up is that you won't make 350kw @ wheels on a Mainline or Dyno Dynamics rolling road dyno using 98 with a GTX3071R.

Ah that makes life simpler. On 98 octane? I can say straight out, a GT4088R is overkill for that power... though these days a GT4088R is pretty much pointless in every way unless you are pretty much given it.

What is the power range you want, and your setup etc? It's hard for anyone to tell you which is better suited when you've mentioned two turbos which flow different to each other. I'm personally not a huge fan of either in the current market, much better options for what both can do out there now.

Cheers mate - that's what I thought. If all other things are pretty close to equal then I'd say it's a STRONG indication that you are out of compressor @Slidewayzzz... or at least very close to it, and should almost consider backing it back slightly as it is. There may or may not be improvements to the setup still by upgrading exhaust and intercooler, however right now probably you won't (or shouldn't) reap the rewards without upgrading the turbo.