Get mine done first!!!!!

 

the EFR turbo is physically longer than traditional turbos (especially integrated WG versions) so it's unlikely to fit most off the shelf manifolds. Full-Race offers an internal WG compatible manifold for the EFR, and we can supply with T3 flange singlescroll or T4 twinscroll, both internal gate only. I have not found a way to keep stock radiator/fan AND internal WG on the EFR, they are mutually exclusive. Pick one or the other for CT9A (evoX has this a bit easier)

the 7064 is a solid turbo, basically a twinscroll 3071R on steroids. Not good for bragging rights, but it can make for a monstrous powerband. make sure your fabricator uses dual wastegates and proper cyl pairing for the 1.05 to do it's thing



here is the dyno chart of the evoX w/ 7670 1.05 a/r. Scott @ Insight built and tuned this car, his comment is that this turbokit/engine combination was a "weapon" - really excited to see it competing at WTAC

for me i really like the 7670 twinscroll powerband, im still considering to run that on my evo instead of the 8374

response from BW engineering:

BorgWarner's compressor maps are corrected to 298K (25C) and 100kPa. In English units, this is 77F and 14.50psia. Most people in the engine industry would agree that this fits the definition of "standard atmospheric conditions". If you ask an aeronautical guy, their answer is a little different.

The Garrett correction factors of 85F and 13.95psia are a bit unusual and I don't know what the origin is. For a correction factor of "1", that would be like a summer day at around 1500' elevation. The reality is that it doesn't matter what the correction factors are as long as the map is accurate and as long as a person is doing a correct match using those factors instead of just tossing around numbers. Our OE customers deal with multiple turbo suppliers and they know their way around these differences. It's a non-issue.


The correction factor difference between these two conditions (77F versus 85F and 14.5psi versus 13.95psi) is 2.7%, not 6% quoted by the writer.

no disrespect, it seems like a bad understanding on your part... no need to jump to conclusions that BW is inflating comp maps. They are good, honest people there. here is some more info for anyone else interested:


On our published 83mm EFR comp map, he is correct, the last island shown is 65%. However, it is easy to extrapolate where the 60% island would be based on where the 65% and 68% islands are. I just sketched it out and I think it's a very reasonable claim to say that the 60% approach and the max-speed approach yields pretty much the same answer. Clearly it depends on what pressure ratio is being used... the guy running a 2.0 pressure ratio will hit 60% efficiency long before he reaches terminal speed. In one area of the map (around 3.0 PR or 30psi boost) the two coincide... at least on a map of this style/shape.

In actual use, there's nothing magic about 60% as a cut-off. Sure, performance starts to diminish as efficiency drops but who's to say where the cut-off is? This is the reason why we publish a map instead of simply saying "this is a 79 lb/min compressor".

 

Good discussion. I think 03white hit the nail on the head with the actual flow numbers being based on different ambient conditions. He came out with the wrong number, but was on the right path. Helps explain the differences from published theoretical to actual dyno numbers we have been seeing. Thanks Geoff for the response!

 

Nice, thank you.
If it came across as insinuating they are trying intentionally to mislead, I apologize. I meant it more like "hey, something ****y is going on here" in more of a skeptical sense. Garrett and BW are using very different conditions and limits to suggest airflow capability though and that is what I was pointing out. And really, let's be realistic, the max airflow is listed clearly on the compressor flow map in an effort to provide a number that people are use to hearing and that number sways the judgement in favor of the BW due to an uneven playing field to the uninformed, intentional or not. I also stated why I believe Garrett uses 13.9 PSI, I imagine it is based on the idea that a typical OEM turbo inlet system is going to have about that range of inlet pressure under service conditions.


But let's get to the rest of the statement where I supposedly don't understand what's going on.

I can admit when I'm wrong, and actually, I did make a mistake here. I pulled those numbers straight out of the matchbot program. Where I made the actual mistake was I had forgotten to zero out the air filter pressure drop setting. My numbers are off, as I basically corrected for 13.75 psia. I apologize for the mistake and will update that chart (taking it down until I get around to it as well) accordingly, however, I understand far better then most how this works, the fact I even mention these subtleties should clue you in to that.

I still disagree with the 2.7% number you posted though. It's actually closer to 4.1% using the matchbot program. Put the numbers in and try it for your self. Either their program is wrong...or hey, I guess I'm still missing a setting in there. This time I was pretty careful to double check it though. Now, I did toss in some numbers really quick to good old PV=mRT to find density as-> P/T = mR/V and interestingly enough, it's a 5.8% difference between the two conditions still...weird.

85F - 13.95 PSIA = 1.1075 kg/m^3
75F - 14.5 PSIA = 1.1727 kg/m^3

1.1727 / 1.1075 = 1.058 or 5.8%

Or (1.1727 - 1.1075)/1.1727 = 5.6%
Or (1.1075 - 1.1727)/1.1075 = -5.9%

I mean, I don't get 2.7% no matter how I look at it. Maybe they can explain where I'm wrong here.

Beyond that though, I never once said either of the turbos reached a true choke flow limit. I simply pointed out the airflow rating you are use to hearing from Garrett are based on the maximum airflow that can be pumped out at 60% efficiency...regardless of pressure ratio and the number printed on the BW charts is not based on the same standards.

Do you dispute that claim?

Also, I don't disagree, Garrett's standard seems arbitrary and 100kPa and 25C is much more standard...but that's not really the point. The point is putting the comparison on a level field, regardless of why it is not level to start with. Also, frankly, I'm surprised I haven't seen this mentioned yet as, really, all we have at this point is compressor flow maps and a few random cars to look at for data. I would think these peculiarities would have been talked about and carefully explained to properly inform potential customers.

 

Who makes the efr turbo ??? Any info available...

 

Seriously? Did you even read the last two posts (not to mention the whole thread)???

BW = Borg Warner = manufacturer of EFR turbos.

l8r)

 

Corrected the mistake I had made previously. I added in turbine flow as well.




As I have mentioned previously, yes, the TiAl wheels are likely a lot lighter for a given wheel diameter...but the Garretts have wheels that are A LOT smaller diameter for a given flow rate. I question how much difference there is in wheel inertia for a given flow requirement. That said, it's pretty likely the EFR wheel being larger will have better overall system efficiency. Let's suppose inertia is even for a given flow rate requirement between the two companies, the EFR wheel should provide better overall performance due to closer wheel tip speeds.

It would be nice to know peak efficiencies on the EFR turbine wheels just to get a rough idea of how they compare to the Garrett wheels. The GT turbine wheels aren't eactly junk when it comes to efficiency...some hitting at high as 74%. They are good wheels, just curious if the EFR wheels out do them.

 

https://www.evolutionm.net/forums/ev...on-s300sx.html #justsayin

 

https://vimeo.com/47358007

Quick iPhone video.... I'll get the go pro out later today

 

Who are you tuned by?

 

Self tuned by a buddy of mine.

Car is running rich. Just rewired the fuel pump, so it's time to go tune some more

 

been lurking as a subaru owner for a long time and really appreciate the activity in this thread as things are much slower on my platform for data.

i'm going for a bit more power but staying with an EFR and am selling my barely used T4 twinscroll IWG 7064 for anyone interested or doesn't feel like waiting for BW to start shipping these again. the FS post in on nasioc - http://forums.nasioc.com/forums/show...php?p=37798615. you can pm me here or there as we all seem to share the passion for this setup on multiple forums, haha.

project_skyline - are you still looking to the end of month for completion with the 8374? i'm eager to see your results!

 

Everyday i'm closer to test out my EFR... now car is back from the Fab shop, it had the front end modded so the radiator can be pulled 1.5in away from the dump tubes for extra clearance. I'll put some pictures of the front and under so you get a better idea of the work that was done.

 

I made boost

http://www.youtube.com/watch?v=obxRZ...ature=youtu.be

 

How does she feel?