I looked at that and my thought was always that the 70/ 0.80 was an obvious mistake .... and they meant to put the 70/1.05 there . But until someone gets that from the horses mouth ................ neither of us know for sure I guess.

look at the progression leading up to that, I would again suggest a possible lack of discernment

Fair point , but those are all equispaced lines and I'm sure they just put them in there to the closest possible match .... We are splitting hairs here though.

I already conceded that it's possibly not suitable for 450 on a 13b but could def. be worthwhile in that 375-425 range..

PS
Is it more discerning to suggest they made two mistakes by not only putting it on the wrong line, but also putting the wrong number ..... or to suggest they just made one mistake by putting the wrong number? ... We could go on all day on this one ...LOL

Anyhoo .............. We know the 7670 is a hot air hair blow drier at that 375-425 level so the 8370 1.05 would def cure that.
We also know that the 8374 would be more efficient in that range than the 8370... but not by a big enough margin to make a noticeable difference.

So in deciding if it's a good solution in that power range it would clearly come down to ...would the 8370 1.05 be much more responsive than the 8374 0.83?
And : is the smaller compressor housing an advantage ?

I think the lines leading up to the blank line and 70mm 0.80a/r mistake track true to expected flow.

The 63mm exhaust wheel is different geometry mixed axial and radial flow designed for the Indycar series and does flow more than the 64mm (standard) radial flow exhaust wheel.

On the 58mm exhaust wheel the 0.80a/r housing is a big dual scroll T4 housing and the two 0.85a/r housings are smaller T25 and tiny T2 v-band housings, so it makes sense they flow the same.

If you only were looking at the 0.83,0.92 ,1.05 progression ........... It would seem logical the 1.05 should go on the blank line . But............... if you put the 1.05 on the blank line you then have to jump TWO lines to get to the 1.22.
You only have to look a few spaces up at the 74mm to see it only jumps ONE line going from a 1.05 to a 1.45.

There are anomalies like that all the way up the chart , which on the face of it don't make sense. But when considering that it's just a series of equispaced lines and none of the turbines will be an exact match ...... it makes perfect sense.

except there is no 1.22 and never has been that I’m aware of

but you’re free to assume anything you want, including that I’m not any more informed about it than you are.
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ok ..so they messed up on several entries , my point still holds .......... neither of us can be 100% sure of what is correct.
Would be nice if BW would correct their mistakes so we didn't have to argue over dumb s**t like this.

no, that’s just more lack of discernment; the only one arguing is you.

try reading it again:

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If you have more information about it ...why not come out with it ?

I just assumed you didn't know much about it from the lack of "discernment" shown in your initial comment talking about the 8370 compressor:

This used to be an interesting thread...

The biggest issue I was concerned about in weighing up 7670 IWG vs 8374 IWG was nothing to do with response. I was always confident 8374 IWG was going to be adequately responsive. The issue is that with a free-flowing exhaust, I faced the possibility of having run to minimum boost of 18-20psi on the 8374 IWG due to the well-documented tendency to overboost. I have no interest in driving around car that is running on 20psi all the time and wanted the flexibility of running a low boost setting for cruising around. This could be fixed with modifying the turbine housing, but then that would adversely affect the responsiveness of the turbo (according to Turblown reducing boost threshold by around 500rpm) - to the point where the difference in responsiveness and the fact I'd need to fiddle around with modifying the turbo did become an issue for me. The other solution of course would be to run a more restrictive exhaust - but then that is just choking up the turbo and also reducing its responsiveness (noting on my car, running LPG, a cat is not required).

If the 8370 can flow a little bit more on the compressor side than the 7670 IWG (which does choke up at higher rpm on a 13B) but without the tendency to overboost like the 8374, then it would be a winner.

Anyone have any thoughts on that?

sorry you feel that way Fendamonkey, there are just many misunderstandings on this forum imo. There was nothing going on in this thread that couldn’t have been accomplished with a Garrett GTX3076. Except since forever everyone on here was convinced and telling anybody who suggested it over and over again it was never going to work, the turbine flows too little etc.

Except the BW came along with a new turbo and nobody was around to say such a thing, and so somebody tried it and what do you know, it was super zippy. Just like a Garrett GTX3076 with 1.06 A/R divided T4 would be. Because where we’re at in this thread right now is people talk about A/R, but they don’t know or understand how that correlates to what actually matters; turbine flow rate. Also, way, way back in the day people tried and old Garrett 3076R and it wasn’t really the same turbo back then. And they were also probably on pump gas rather than E85 or C16 race gas, had a poor setup, poor ecu/tuning ability, poor timing map, poorly biased WG, etc. etc.


https://cimg1.ibsrv.net/gimg/www.rx7...f70f5d154.jpeg
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https://cimg2.ibsrv.net/gimg/www.rx7...3aa411491.jpeg
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so one of the most winning autox cars I know of is Jeff Kiesel’s EMod Bugeye Sprite with a 13B turbo. He used to have a 20B NA PP, but the late Jim Mederer from Racing Beat built him this 13B Turbo setup 14 -15 years or so ago. The car only weighs 1800 lbs. and is setup with 4 or 5 boost settings to make 300 - 400 whp; race gas or E85 of course, but he generally doesn’t run more than 350 whp because at that weight it will spin the huge rear slick race tires easily. The thing is this; it only has a Garrett GTX3071 turbo with 0.83 A/R housing (~23 lb/min). You know, the turbo everybody on here would scream and call you an idiot for choosing:


https://www.garrettmotion.com/news/n...austin-healey/

https://www.racingbeat.com/mazda/per...ff-kiesel.html


Let me explain something; I don’t have to prove anything to anybody. You don’t want to believe what I’m sharing with you, want to believe I have no idea what I’m talking about, whatever. I don’t care. People are free to believe what they want. There’s nothing I have or know that isn’t available to anyone who makes an effort to find out on their own. Or just bury your head in the sand and play Polly Parrot repeating the same old mantra that “it will never work”. Whatever is going on in anyone else’s head is not my problem at all.
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AES exhaust butterfly on a small parallel section of exhaust (heavier, dulled response to lower target boost), or a BOV and MAC valve (or a spare OEM solenoid) with alternate manifold or atmospheric reference for partial intake wastegating (lighter, no impact on response until it cracks), shouldn't be difficult to do in modern ecu logic or just a trigger switch.

Given the EFR comes with a BOV and you will probably have spare OEM solenoids you are out of pocket a few dollars if you buy new plug and pins, or nothing if you reuse a bit of factory loom.

For a more natural top end torque curve on even a mildly ported or standard later 13b I would prefer the 74mm turbine if I was shelling out for an EFR, unless the car was specifically for autocross/short hillclimb or similar.

Why are you referencing a highly custom vehicle running on race gas to demonstrate that the old Garrett can meet the needs here?

Seems totally irrelevant. The majority of FDs are mostly street cars running under 18 psi of boost (likely less than that). The EFR came out 10 years ago. I'm sure Garrett has finally caught up. But to reference a car built 15 years ago specifically for racing and using race gas for high boost makes no sense.

At this point he appears to be arguing simply for the sake of arguing so he can feel correct.

Just for fun, here's some EFR power. ACME Special, fastest autocross car ever, by a wide margin (10+ seconds raw time faster than the nearest competitor at Nationals)

it has nothing to do with me being correct, the results are what they are and it will generate the same output regardless of the vehicle.

otherwise I’m not going to care about your bellyaching, it’s not like there’s anything else interesting going on in here lately.

so getting back to the actual thread; I found a supplier for an aftermarket divided twin scroll EWG turbine housing for fitment on an EFR7163 with an A/R that should have a little better peak flow capacity than the EFR7670 1.05 housing. It should then provide EFR7670 performance in a hybrid B1 frame package. That will be for a future Renesis project though.

on my own RX8-REW project I chose a Garrett G30-770 with 1.06 twin scroll for a quick boosting 450-500 whp goal. So if somebody goes for the new EFR8370 maybe we can get some comparison results going in the future.
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no, the guys still stuck back in their experience and comprehension level I can appreciate not knowing any of this, but it was shared with you a year or so ago and apparently you never bothered to challenge yourself like you do me and expand your own understanding on it.

so let me help you out with it by posting the chart below; can you now please explain how or why the 70mm turbine would suddenly jump two flow lines going from 0.92 to 1.05 A/R when even the next size larger 74 mm turbine doesn’t do that, but instead progresses steadily going from 0.92 to 1.05 A/R just like the smaller 64mm B2 frame turbine did before it? :dunno:


https://cimg6.ibsrv.net/gimg/www.rx7...e79a222a0.jpeg



so I’d again suggest that while there will be some improvement around the low 400 whp range over a 7670, that the 70mm turbine is going to struggle spinning an 83mm compressor when choking on the higher rotary turbine flow requirement. I’m not trying to compare against what the average FD owner might do, but against what was done here in this thread with the 7670. The example I posted above regarding the Garrett isn’t running high boost like the 7670 here was. The point that it was intended to make was apparently lost on some people.

Because it’s going to take high boost and E85 or other octane compensation to get that low rpm torque curve on a 7670 like Blue did. Otherwise don’t even bother, because as he himself explained in this thread and is demonstrated by some of the other 7670 results; running lower boost on the 7670 was a bit bland and lacking. The wick had to be turned up for it to come alive and produce that result. That means the new 8370 will require it too and more is likely needed to drive it there. If you’re not going to do that then just get the 8374 0.92 instead and try to keep the rpms up.
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I did already explain it above but here it is visually for you. Could do the same with the others you mentioned to explain why they didn't jump a line .

https://cimg4.ibsrv.net/gimg/www.rx7...44ce519ab5.jpg

Was quite happy to let this die(because as others have pointed out ... it's dumb) but seeing as you asked me directly ...............

What I notice is BW offers 0.83ar, 0.92ar, 1.05ar and 1.45ar exhaust housings for the 70mm exhaust wheel.

They dont make an 0.80ar exhaust housing for the 70mm exhaust wheel.

The 1.45ar exhaust housing could slot in the chart where it says .80ar 70mm exhaust wheel.

Furthermore, it looks to me like the turbine flow line missing a label would be the 1.05ar 70mm exhaust wheel combo BW makes and is missing from the chart.

Could be that .... and that does look more likely to be fair.
I'm just defending myself against Teams' vitriol by showing how it could also be what I suggested initially.

^^I regret that you see it as such, but you’re just not correct in your assessment and likely refusing to accept it out of your own internal bias against who it is trying to correct you on it.



only partially correct; they’ve never made or offered a 0.80, 1.22, or 1.45 A/R housing for the EFR 70mm turbine.

https://cimg3.ibsrv.net/gimg/www.rx7...225035a44.jpeg


https://cimg0.ibsrv.net/gimg/www.rx7...00c806915.jpeg

some of the confusion is likely due to the housings offered on the S200 SX-E 70mm turbine housings:


https://cimg7.ibsrv.net/gimg/www.rx7...3f20ca11a.jpeg

which btw there is an S261 SX-E offering that most people are not aware of; it has the S362 compressor wheel in the S200 compressor housing, likely good to ~500 whp range on a 13B. Because unlike the new EFR8370, you can see in the S200 SX-E listing above that there are higher A/R turbine housings available to support it flowing enough.

want to split it evenly between 0.92 and 1.22, then here you go:

70mm 1.22 - 28.5 lb/hr

70mm 1.15 - 27.6 lb/hr

Incorrect 0.80 Line - 27.0 lb/hr

70mm 1.09 - 26.7 lb/hr

70mm 1.05 - 25.8 lb/hr

Blank Line - 25.5 lb/hr

70mm 1.00 - 24.9 lb/hr

70mm 0.92 - 24.0 lb/hr

———————————————

not entirely off topic, but I just recently had an aftermarket EWG turbine housing fitted to an EFR7163 to create a 7670 hybrid in a smaller B1 frame configuration. It’s a divided T3, but with the 63mm/55mm turbine wheel is not really any issue wrt flow potential. At the moment it’s hung up in shipping due the current winter storm, but they sent me a pic of it below next to the original 0.80 IWG housing. It has a 1.25 A/R, which should get it in the 7670 turbine flow range. It’s only available in cast iron though. Will be putting the larger SX-E compressor cover on it as well.


https://cimg0.ibsrv.net/gimg/www.rx7...318fdf014.jpeg

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I am the one that ran the test on this... The owner of the car was already running a BOV and liked the idea of real turbo sounds, while making it more efficient. It definitely made more power, all things the same, while spooling more quickly... On the dyno. On the street, the spool was about the same, though it likely makes more power during the whole boost threshold of "spooling". I know, based on the same forum you found these results, there are other people wanting to try different covers on other EFR turbos. I had an EFR 6758 on my STi and I loved that it had the BPV and a decent IWG (with added 2-port actuator and 4-port EBCS), for simplicity. I also went this route on my track car, which is an S2000 with and EFR 7064, utilizing the IWG and BPV. Ultimately, the setup I did with this turbo made the power I wanted, with little effort (8 PSI flat).

https://cimg4.ibsrv.net/gimg/www.rx7...2aa91a95ca.jpg

The full video of our EFR/SX-E testing can be seen here:



Maybe not the latest and greatest news, but I had heard for years that swapping covers on a 7163 was a 10% increase in efficiency. One of my friends (and customers of which I tune their 8-second Ford Taurus), has and EFR 7163 on his jetski and swapped to the SX-E cover and swore by the increase, so when the chance arose, we tested it.

Thats funny, was looking at that 1.25ar divided t3 housing for my efr 7163 too.

Like Team I am thinking 7163 cause I have one.

In addition, Im too poor to do full single in one step and it would work with my stock ROM tune ECU/stock fuel system while leaving an upgrade path to a real single turbo upgrade.