|
|
|
|
Thread Tools | Display Modes |
10-07-2013, 10:14 AM | #501 |
NASIOC Vendor
Member#: 198281
Join Date: Dec 2008
Chapter/Region:
MAIC
Location: Virginia
Vehicle:2005 WRX/STi WRB of course |
FYI... non-IWG housing w/EWG>IWG housing w/EWG>IWG housing w/IWG.
Nothing beats the performance of a smooth round (expanding) shape as gasses exit the turbine/wheel. I can't think of any argument where a turbine outlet with features in it offers improved performance.
* Registered users of the site do not see these ads.
|
10-07-2013, 10:19 AM | #502 |
Scooby Specialist
Member#: 330625
Join Date: Aug 2012
Chapter/Region:
NESIC
Location: MA
Vehicle:2006 WRX WRB |
I'm not saying its better, but the difference in performance between the efr iwg and an efr with an ewg will be so minimal that it will caught up in the dyno's margin of error. In theory there should be a difference, but IMO it wont be noticeable in real life. BW made a lot of packaging sacrifices with the turbine housing by making the iwg the way they did, they wouldnt have done that without there being a significant benefit.
|
10-07-2013, 10:51 AM | #503 |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
^^^^^^^^^^^^^^^
|
10-07-2013, 11:03 AM | #504 |
Scooby Newbie
Member#: 217648
Join Date: Jul 2009
Chapter/Region:
BAIC
Location: NOR CAL
|
I think we all know that a proper ewg vented to atmosphere is better, by how much idk... Now nobody is arguing that... They are simply saying that iwg is nearly as efficient as ewg plummed back into exhaust... There not saying it's better, just that it is close enough that it's not worth it for the $ in saving and the space it will occupy... Am I right to assume this is what you mean?
|
10-07-2013, 11:11 AM | #505 | ||
Scooby Specialist
Member#: 193757
Join Date: Nov 2008
Chapter/Region:
MWSOC
Location: Cedar, MI HP Techs MPS-SSLR2.5
Vehicle:2006 XTI Limited OBP, Junior tuned 573WHP |
Quote:
Quote:
|
||
10-07-2013, 11:27 AM | #506 | |
NASIOC Vendor
Member#: 198281
Join Date: Dec 2008
Chapter/Region:
MAIC
Location: Virginia
Vehicle:2005 WRX/STi WRB of course |
Quote:
Without a before/after true test with the EFR housings it's all a moot point, but what I said is fairly well understood and proven on many other housing style over the years. With the older Garrett housings vs Tial, there was a clear measurable performance edge. As was the continuation of the turbine piping with straight tube, expanding (megaphone) to straight, and/or having straight or a 90° bend shortly after the exit of the turbine. Pre or post turbulence has an effect on efficiency. Minor difference will show negligible differences in output, but there are (from what we've experienced) measurable/repeatable difference in a housing made for the masses with a built in IWG, and a performance based housing. IMO the EFR housing is certainly an improvement over their previous offering, arguably the best IWG currently on the market right now. |
|
10-07-2013, 11:38 AM | #507 |
Scooby Specialist
Member#: 330625
Join Date: Aug 2012
Chapter/Region:
NESIC
Location: MA
Vehicle:2006 WRX WRB |
I think they weighed much more heavily on performance than you think. They've had problems with the complexity of the housings and having them produced, which is why my housing is a somewhat ugly sand casting rather than one of the beautiful investment cast housings. And the extra length from this iwg setup actually makes fitting these things in an engine bay a major pain in the ass. But still easier than a lot of ewg setups.
|
10-07-2013, 07:46 PM | #508 |
Scooby Newbie
Member#: 156635
Join Date: Aug 2007
Chapter/Region:
NWIC
Location: Puget Sound
Vehicle:2005 Sti CGM |
I feel like I must be taking stupid pills, because I don't get the EWG vs IWG debate as it pertains to these EFR turbos. Have we yet seen an IWG EFR turbo on a suby 2.5L that hasn't had issues holding boost to redline? Stiff spring and proper preload accounted for, they still blow open it would seem.
|
10-07-2013, 08:06 PM | #509 |
Scooby Newbie
Member#: 217648
Join Date: Jul 2009
Chapter/Region:
BAIC
Location: NOR CAL
|
I believe that's due to running out of air... not air escaping through iwg
|
10-07-2013, 09:19 PM | #510 | |
Scooby Newbie
Member#: 156635
Join Date: Aug 2007
Chapter/Region:
NWIC
Location: Puget Sound
Vehicle:2005 Sti CGM |
Quote:
There have still been other builds with the larger IWG EFR turbos that have ran into problems holding boost till redline though. So it doesn't appear to be a one time fluke on our 2.5L engines. Or.........no one in the community (Perrin included) knows how to set these IWG turbos up. |
|
10-07-2013, 09:32 PM | #511 |
Scooby Newbie
Member#: 217648
Join Date: Jul 2009
Chapter/Region:
BAIC
Location: NOR CAL
|
That's what I though... but I'll have to leave the conclusion to those with more experience with these turbos than I
|
10-07-2013, 10:36 PM | #512 |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
http://www.turbodriven.com/performan...bot/index.html -- this web page can answer a lot of questions, if youre willing to take the time required to read a compressor map. When i started working with BW we demanded they present WAY MORE data for these turbos than anything else out there, so enthusiasts can see numerically what each turbo could do on your engine before making a decision. One fact many turbo enthusiasts dont understand is: if your compresor wheel is out of breath OR if your turbine is at capacity, you cant keep making boost, it will drop. Sure you can overspeed a turbo to a certain limit, but it doesnt matter how stiff your WG spring is (or welded shut with no WG) there will be a wall that gets hit eventually, depending on VE, boost level and RPM.
i encourage you to spend an afternoon with matchbot, it clears up a lot of questions. for example, HERE is a 2.5L Subaru with EFR6758 example i just tossed together: http://i.imgur.com/A702iUo.png you can see most of the points are on the map, and only the very topmost red dot #6, 7000rpm, is just over the edge. This EFR6758 is a great combination for a stock STI and 6 speed trans, becuase you are truly using all of the map! its rated 53lb/min at full tilt, and 7000rpm 2.5L and 20psi asks about 54lb/min airflow requirement, so its not a stretch and barely entering overspeed compare that to the EFR6258 and 2.5L combination @ 20psi http://i.imgur.com/HvqckRN.png and you can see its off the map above 6000rpm at 20psi even though it tapers to 17psi we would be operating in overspeed at that 7000rpm redline. While this turbo does work wonders on the subaru engines we've tested it on (case in point jager racing is breaking records in their class) you wouldnt want to rev beyond 7000rpm at full tilt or hold it there, however it does get a torque kick so my #1 reocmendation on a 5EAT setup. Try this same comparison on a 2.0L and everything changes of course Last edited by Full-Race Geoff; 10-07-2013 at 10:45 PM. |
10-07-2013, 11:05 PM | #513 |
Scooby Guru
Member#: 32669
Join Date: Feb 2003
Chapter/Region:
SCIC
Location: Woodland Hills
Vehicle:2007 2.34LR, EFR7670 LINK G4+ hybrid STi |
I guess we will see how hard it is to make big boost with the IWG when my new motor gets wrapped up. The last build hit 18 psi pretty easily with very little preload and only about 50% WGDC. Never had problems holding boost flat but I still haven't targeted the big boost yet.
I'm running the 7670 on a Full Race kit. Ran about 7,000 miles on a 2.5L, soon to be a 2.34L and 8K rev limit. |
10-07-2013, 11:20 PM | #514 |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
^^kelly, read the thread above, this is a great opportunity to look at how compressor maps work. lets look at the matchbot of your 2.34L engine from 3000-8000rpm and EFR7670 combination and a 30psi target since most people consider 2bar 'big boost'
http://i.imgur.com/QkUTlYB.png the EFR 7670 compressor wheel is kicking major butt on your motor, until 7000+rpm. at this point you are beginning to run the compressor off the map and enter turbocharger overspeed condition either reduce boost to ~25psi above 7000rpm or dont rev quite as high, let the powerband determine this. http://i.imgur.com/kbPiKfw.png if you are targetting stable power at the higher rpm and higher boost levels the EFR8374 would be the call http://i.imgur.com/fKjqlBw.png all points fit comfortably on the map, with room to spare |
10-07-2013, 11:43 PM | #515 |
Scooby Guru
Member#: 32669
Join Date: Feb 2003
Chapter/Region:
SCIC
Location: Woodland Hills
Vehicle:2007 2.34LR, EFR7670 LINK G4+ hybrid STi |
I'm happy with 25 psi on 91 + meth everyday.
Maybe 8374 when I'm bored with that. |
10-07-2013, 11:44 PM | #516 |
Scooby Newbie
Member#: 156635
Join Date: Aug 2007
Chapter/Region:
NWIC
Location: Puget Sound
Vehicle:2005 Sti CGM |
Noob matchbot question for you Geoff: Would we want to estimate on the lower side of VE for our head design in conjunction with our miles of pre-turbo manifold track and UEL pulsing?
|
10-07-2013, 11:50 PM | #517 | |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
Quote:
yes a good flowing exhaust manifold will help VE go up just like a bad one will make it drop. All the data i have collected over the years is with Full-race lower manifolds (we do virtually zero testing on the stockers) so I cant really say what the VE #s would settle at for you. the values i used are pretty accurate for a stock sti motor and header/up pipe/3" exh |
|
10-08-2013, 12:18 AM | #518 |
Scooby Guru
Member#: 32669
Join Date: Feb 2003
Chapter/Region:
SCIC
Location: Woodland Hills
Vehicle:2007 2.34LR, EFR7670 LINK G4+ hybrid STi |
Well I'm headwork + cams and a lot of PnP. How much do you think I can tweak the VE by?
|
10-08-2013, 12:23 AM | #519 |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
some engines can get over 110%, turbo s2000s ive seen close to 113-114%. i can not comment on what your specific engine is capable of, the best way to do that is work backwards once you have results. BorgWarner's turbo shaft speed sensor is VERY helpful in determining this!
|
10-08-2013, 12:34 AM | #520 |
Scooby Guru
Member#: 32669
Join Date: Feb 2003
Chapter/Region:
SCIC
Location: Woodland Hills
Vehicle:2007 2.34LR, EFR7670 LINK G4+ hybrid STi |
I had ordered the speed sensor but had to send it back because I couldn't get it to fit the way I have the compressor clocked. To bad too, I have sensors to measure FMIC inlet and outlet temperature and pressures so we could get some good FMIC data to work backwards with in matchbot.
|
10-08-2013, 08:27 AM | #521 | |
Scooby Specialist
Member#: 144751
Join Date: Mar 2007
Chapter/Region:
MWSOC
Location: Granger, IN
Vehicle:02 WRX BW EFR E85 7064 TS WRB |
Quote:
|
|
10-08-2013, 12:44 PM | #522 |
Scooby Specialist
Member#: 158888
Join Date: Sep 2007
Chapter/Region:
MAIC
Location: Baltimore area
Vehicle:2011 STi EFR 7163! 07 GT30 WRX sold :/ |
I am going to forgive BW for the delay on the release of this turbo. They must be victim of the Govt Shutdown!
|
10-08-2013, 04:09 PM | #523 | |
Scooby Specialist
Member#: 96204
Join Date: Sep 2005
Chapter/Region:
W. Canada
Location: Winnipeg
Vehicle:2013 STI GR White |
Quote:
What really matters is what boost? And 2.0 or 2.5? W/o the above info holding boost red-line is meaningless. |
|
10-08-2013, 06:09 PM | #524 |
Scooby Specialist
Member#: 225268
Join Date: Sep 2009
Chapter/Region:
MAIC
Location: Ohio
Vehicle:2005 STI WRB |
6758 doesn't hold till redline I know that on a 2.5 @23psi
|
10-08-2013, 06:18 PM | #525 |
Scooby Specialist
Member#: 133386
Join Date: Nov 2006
Chapter/Region:
SWIC
Location: AZ/NJ
Vehicle:00 too many turbos white |
read the post above: http://forums.nasioc.com/forums/show...&postcount=512
max boost at redline on the 6758 for a 2.5L engine is around 19-20psi. its not that "it doesnt hold" -- it's that you are trying to overspeed the turbo... if you want power up there you need a bigger snail #factsoflife |
Thread Tools | |
Display Modes | |
|
|