Welcome to the North American Subaru Impreza Owners Club Sunday April 26, 2015
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC General > Proven Power Bragging

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 10-08-2013, 06:35 PM   #526
LittleBlueGT
Scooby Specialist
 
Member#: 96204
Join Date: Sep 2005
Chapter/Region: W. Canada
Location: Winnipeg
Vehicle:
2013 STI GR
White

Default

Quote:
Originally Posted by RobSTI89 View Post
6758 doesn't hold till redline I know that on a 2.5 @23psi

FWIW pretty much ANY turbo cannot hold boost to red-line assuming mid-range boost is raised.

A VF will hold 15 psi at red-line, but it drops off cause we ask for 19 or so in the mid-range area.

A 35R can hold 25 psi at red-line, but not 32psi (which it can easily do in the mid-range, block, well, not soo much).
* Registered users of the site do not see these ads.
LittleBlueGT is offline   Reply With Quote
Old 10-08-2013, 06:53 PM   #527
Leafy
Scooby Specialist
 
Member#: 330625
Join Date: Aug 2012
Chapter/Region: NESIC
Location: MA
Vehicle:
2006 WRX
WRB

Default

Quote:
Originally Posted by Full-Race Geoff View Post
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
Pretty much. And I mean its like like its a VF or a td04 falling off a cliff here. Its making some serious ****ing power even if you're tapering off. Just feel lucky that subaru tuners have figured out that you can run different amounts of boost at different PRMs, theres still plenty of car groups out there that would say the 6758 is only good for 20psi on a 2.5 and just run 20 straight across the board rather than maximizing area under the curve by using all the compressor map.
Leafy is offline   Reply With Quote
Old 10-08-2013, 07:37 PM   #528
Concillian
Scooby Guru
 
Member#: 4414
Join Date: Feb 2001
Location: Dublin, CA
Vehicle:
2002 WRX Sedan
Midnight Black

Default

People seem really concerned about "holding boost to redline", but ultimately area under the curve is a bigger deal and it's more "flow vs RPM" Sure a 6758 only holds 19-20psi to redline on a 2.457 liter, but it's flowing close to 50-53 lbs/min with very nearly stock turbo spool.

Matchbot at constant boost is interesting, but what someone with a strong enough tranny (not me) would want to do is run 25+psi in the midrange so tehy hit that 50-53 lbs/min before redline and keep that flow for 1000 RPMs or so. What matters is peak flow for the engine and how broadly can flow be applied.

Now when dealing with other limitations, like:
- 91 octane safe boost level,
- or wanting to stay under the stock MAP sensor,
- or wanting to maintain a torque level that won't shred a 5MT
then straight across maps make some sense, but people building for motorsports wouldn't necessarily limit boost to peak flow boost on the engine. Like mentioned with the vf and TD04, there's plenty to be gained by reaching the flow limit early and letting boost taper.
Concillian is offline   Reply With Quote
Old 10-08-2013, 08:54 PM   #529
thefoos
Scooby Specialist
 
Member#: 144751
Join Date: Mar 2007
Chapter/Region: MWSOC
Location: Granger, IN
Vehicle:
02 WRX BW EFR E85
7064 TS WRB

Default

Quote:
Originally Posted by LittleBlueGT View Post
What really matters is what boost? And 2.0 or 2.5?

W/o the above info holding boost red-line is meaningless.
I wasn't arguing target boost, I was arguing control. There have been a number of times this has come up, and I don't get it. Folks claiming these are difficult to control....perhaps I misunderstood this current discussion.

Link if you want info...
http://forums.nasioc.com/forums/show....php?t=2356854

I didn't document it here, but I ran, in a controlled fashion, up to 35 psi...

Personally, I like running a turbo that most consider too small. Effectively reach a target air flow and have a nice, flat, power curve. Peaky torque. That means tapering boost. Also means having an engine that is far more responsive at low throttle, low rpm. Things you don't see on a dyno sheet. I'd be looking at a 6258 or 6758 on a 2.5L myself. That can head off topic though...

Last edited by thefoos; 10-08-2013 at 09:01 PM.
thefoos is offline   Reply With Quote
Old 10-08-2013, 09:08 PM   #530
manitou
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

Default

Quote:
Originally Posted by LittleBlueGT View Post
FWIW pretty much ANY turbo cannot hold boost to red-line assuming mid-range boost is raised.

A VF will hold 15 psi at red-line, but it drops off cause we ask for 19 or so in the mid-range area.

A 35R can hold 25 psi at red-line, but not 32psi (which it can easily do in the mid-range, block, well, not soo much).
I wouldn't say that's a true statement. I have a 58lb. turbo that holds 28 or 29 psi depending on the gear from 4K to redline. My target boost is pretty much the same from midrange out. I personally don't like the spike and fall style of tuning that you describe above.
manitou is offline   Reply With Quote
Old 10-08-2013, 09:10 PM   #531
Leafy
Scooby Specialist
 
Member#: 330625
Join Date: Aug 2012
Chapter/Region: NESIC
Location: MA
Vehicle:
2006 WRX
WRB

Default

Quote:
Originally Posted by manitou View Post
I wouldn't say that's a true statement. I have a 58lb. turbo that holds 28 or 29 psi depending on the gear from 4K to redline. My target boost is pretty much the same from midrange out. I personally don't like the spike and fall style of tuning that you describe above.
Right, but I bet it could make 32 in the mid range and wouldnt be able to hold it to redline, which is exactly what the statement you bolded is saying. It also sounds like the turbine on that turbo you have is too small.
Leafy is offline   Reply With Quote
Old 10-08-2013, 09:36 PM   #532
manitou
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

Default

It probably could make 30-32ish in the mid range but why? It's better to tune for averages and build a smooth progressive power band. The turbine is not too small, my housing at 8cm might be a touch small on the top end but I'm making almost 600whp with a 58lb. turbo so that's even debatable!
manitou is offline   Reply With Quote
Old 10-08-2013, 09:59 PM   #533
3mlwhly
Scooby Newbie
 
Member#: 217648
Join Date: Jul 2009
Location: NOR CAL
Vehicle:
01 2.5rs

Default

No way that's a 58lb turbo.. NO WAY
3mlwhly is offline   Reply With Quote
Old 10-08-2013, 10:26 PM   #534
manitou
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

Default

Quote:
Originally Posted by 3mlwhly View Post
No way that's a 58lb turbo.. NO WAY
Really, it's a Blouch 3.5xtr. Maybe it's underrated! Lol
manitou is offline   Reply With Quote
Old 10-08-2013, 10:27 PM   #535
3mlwhly
Scooby Newbie
 
Member#: 217648
Join Date: Jul 2009
Location: NOR CAL
Vehicle:
01 2.5rs

Default

thats alot of whp for that turbo, idk then?
3mlwhly is offline   Reply With Quote
Old 10-08-2013, 10:31 PM   #536
3mlwhly
Scooby Newbie
 
Member#: 217648
Join Date: Jul 2009
Location: NOR CAL
Vehicle:
01 2.5rs

Default efr

deleted

Last edited by 3mlwhly; 10-08-2013 at 10:35 PM. Reason: my ignorance
3mlwhly is offline   Reply With Quote
Old 10-09-2013, 12:09 AM   #537
Full-Race Geoff
Scooby Specialist
 
Member#: 133386
Join Date: Nov 2006
Chapter/Region: Tri-State
Location: AZ/NJ
Vehicle:
13 F150
ecoboost

Default

assuming its based on a garrett compressor, the map should be available and you can plot it roughly on matchbot..
Full-Race Geoff is offline   Reply With Quote
Old 10-09-2013, 12:32 AM   #538
RobSTI89
Scooby Specialist
 
Member#: 225268
Join Date: Sep 2009
Chapter/Region: MAIC
Location: Ohio
Vehicle:
2005 STI
WRB

Default

I tried to get a bigger turbo lol but someone didn't release it in time. Hopefully bw will offer a trade in program when they release this 7163
RobSTI89 is offline   Reply With Quote
Old 10-11-2013, 09:29 AM   #539
Obababoy
Scooby Specialist
 
Member#: 158888
Join Date: Sep 2007
Chapter/Region: MAIC
Location: Baltimore area
Vehicle:
2011 STi EFR 7163!
07 GT30 WRX sold :/

Default

Quote:
Originally Posted by LittleBlueGT View Post
FWIW pretty much ANY turbo cannot hold boost to red-line assuming mid-range boost is raised.

A VF will hold 15 psi at red-line, but it drops off cause we ask for 19 or so in the mid-range area.

A 35R can hold 25 psi at red-line, but not 32psi (which it can easily do in the mid-range, block, well, not soo much).
Bit off topic but there isn't much progress with this right now and im curious. .. I know this is a Subaru forum so we assume we are talking about ~2.0 and ~2.5l but wouldn't the size/displacement of an engine also change be a determining variable in how a turbo holds boost?
Obababoy is offline   Reply With Quote
Old 10-11-2013, 10:24 AM   #540
3mlwhly
Scooby Newbie
 
Member#: 217648
Join Date: Jul 2009
Location: NOR CAL
Vehicle:
01 2.5rs

Default

Yes that has been talked about here... More displacement means you need a bigger turbo to hold more boost longer, or if you use small turbi, boost will drop at redline, if you go back about a week or two in this thread it was being discussed
3mlwhly is offline   Reply With Quote
Old 10-11-2013, 08:48 PM   #541
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg "2+" 300hp/360trq

Default

Ok. So this is a TAD off topic and I apologize in advance but this seemed to be a decent place to ask.

I have a 2010 WRX (2.5L) with 99.75mm Manley forged pistons and ARP head studs, but otherwise the motor is stock internally. Stock rods, stock heads stock cams, etc. I currently have a full-race 1.5 scroll stock location header on the stock vf52 turbo, but going to a different flange is as easy as modifying my up-pipe, and going TS would be as easy and swapping in a different up-pipe. Current setup is making 310/375 SAE.

This won't be for a while but I'm trying to think of my future setup.

Thinking about wanting 400whp/400trq or so and as fast of spool as I can get, stock like spool will be Ideal. Not looking to really try for any high RPM stuff, no more than 6500-7000rpm, more than that and I think I'll need to pull the motor again and put some head work into it and that's just not in my plan for now.

I'm also heavily leaning towards something IWG, and since these EFR turbos seem to not really have any creep issues, and are making good power and fast spool, it's piqued my interest.

So the question is, 6758 or 6258? Stock location (like in the first post) not rotated. Want to use my Speaco TMIC (possibly modified for fitment) not FMIC.

Seems the 6758 is a popular choice for the 2.5L, makes more power, and more power in the top end and had a tad more lag. The 6258 seems to make less power (more along the lines of the power point I'm looking for) but much faster and stock like spool and a popular choice for 2.0L

So what do you think?

Do the 6258 and get the power point and spool I'm looking for and accept the top end loss? Or do the 6758 and "de-tune" it with less boost to get my the power I'm looking for and have better power to redline?
gsrcrxsi is offline   Reply With Quote
Old 10-11-2013, 09:31 PM   #542
Concillian
Scooby Guru
 
Member#: 4414
Join Date: Feb 2001
Location: Dublin, CA
Vehicle:
2002 WRX Sedan
Midnight Black

Default

if you're talking pump gas, I don't really see the 6258 getting to 400 WHP. E85 it can get there. If talking E85, then 6258 has potential for 400 on a dynojet type dyno calibration.

I'd use 6758 on pump if 400 WHP is your goal. It only loses 1-200 RPM spool from the stock turbo. Barely noticeable loss in spool. I don't think you need to do much "de-tuning" a 6758 to get 400 WHP on pump. A true 400 WHP on pump needs some push. How much boost do you really want to run on pump gas?

Last edited by Concillian; 10-12-2013 at 01:07 AM.
Concillian is offline   Reply With Quote
Old 10-11-2013, 10:00 PM   #543
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg "2+" 300hp/360trq

Default

Thanks for the reply. And yes I'm talking pump gas. Unfortunately E85 is not available in my area. and i also noticed that the first post was on E85/91. power estimates of the 7163 on 93? how does the 7163 compare to the 6758 and 6258? inbetween them?

I also got a PM from another member who made 410/420 on pump (mustang dyno) on the 6758 with a 2.5L, though he had cams and some other work as well.

One last q, Are there any EFR Twin scroll candidates in this power range and spool that will fit non-rotated? IWG Please.

Last edited by gsrcrxsi; 10-11-2013 at 10:22 PM.
gsrcrxsi is offline   Reply With Quote
Old 10-11-2013, 11:09 PM   #544
LittleBlueGT
Scooby Specialist
 
Member#: 96204
Join Date: Sep 2005
Chapter/Region: W. Canada
Location: Winnipeg
Vehicle:
2013 STI GR
White

Default

Quote:
Originally Posted by gsrcrxsi View Post
Ok. So this is a TAD off topic and I apologize in advance but this seemed to be a decent place to ask.

I have a 2010 WRX (2.5L) with 99.75mm Manley forged pistons and ARP head studs, but otherwise the motor is stock internally. Stock rods, stock heads stock cams, etc. I currently have a full-race 1.5 scroll stock location header on the stock vf52 turbo, but going to a different flange is as easy as modifying my up-pipe, and going TS would be as easy and swapping in a different up-pipe. Current setup is making 310/375 SAE.

This won't be for a while but I'm trying to think of my future setup.

Thinking about wanting 400whp/400trq or so and as fast of spool as I can get, stock like spool will be Ideal. Not looking to really try for any high RPM stuff, no more than 6500-7000rpm, more than that and I think I'll need to pull the motor again and put some head work into it and that's just not in my plan for now.

I'm also heavily leaning towards something IWG, and since these EFR turbos seem to not really have any creep issues, and are making good power and fast spool, it's piqued my interest.

So the question is, 6758 or 6258? Stock location (like in the first post) not rotated. Want to use my Speaco TMIC (possibly modified for fitment) not FMIC.

Seems the 6758 is a popular choice for the 2.5L, makes more power, and more power in the top end and had a tad more lag. The 6258 seems to make less power (more along the lines of the power point I'm looking for) but much faster and stock like spool and a popular choice for 2.0L

So what do you think?

Do the 6258 and get the power point and spool I'm looking for and accept the top end loss? Or do the 6758 and "de-tune" it with less boost to get my the power I'm looking for and have better power to redline?
The 1.5 scroll header will not bolt up to an OEM style UP, therefore it will not work with the SS 6258 or 6758.

Sorry.

You do have this header, right?






That will work with their TS turbos assuming you change the UP. The 6258 or 6758 don't fit that bill right now.
LittleBlueGT is offline   Reply With Quote
Old 10-11-2013, 11:40 PM   #545
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg "2+" 300hp/360trq

Default

Yes that's the header. I would modify the up-pipe to the T25 flange. Cut off the stock flange, weld on the T25. Or fabricate (or have full-race make) a new 1.5 scroll up-pipe with the T25 flange.

I understand that the flange is different. That's why I mentioned that I would need a new up-pipe or modify mine to work.

But that's not really the point I was asking. Seems both the PM I recieved and the reply from Concillian point to the 6758 being the better option.

Unless you have a TS IWG option to suggest?
gsrcrxsi is offline   Reply With Quote
Old 10-12-2013, 01:19 AM   #546
Concillian
Scooby Guru
 
Member#: 4414
Join Date: Feb 2001
Location: Dublin, CA
Vehicle:
2002 WRX Sedan
Midnight Black

Default

Quote:
Originally Posted by gsrcrxsi View Post
Thanks for the reply. And yes I'm talking pump gas. Unfortunately E85 is not available in my area. and i also noticed that the first post was on E85/91. power estimates of the 7163 on 93? how does the 7163 compare to the 6758 and 6258? inbetween them?

I also got a PM from another member who made 410/420 on pump (mustang dyno) on the 6758 with a 2.5L, though he had cams and some other work as well.

One last q, Are there any EFR Twin scroll candidates in this power range and spool that will fit non-rotated? IWG Please.
Yeah, the 7163 in the first post was a previous revision. It's going to end up different. That car was also fairly restricted with stock exhaust, TGVs and Stock TMIC. I'm sure it will be a different beast in the release version.

To be honest I see the 6758 being easily in that same territory if pushed on a car that has better supporting mods than the car in the first post. I might get 400 on pump in less restrictive. I'm at 420ish on E85 and I'm out of injector, but the turbo has more in it. It definitely has some oomph.

No twin scroll for the small frames. Don't know that it's a big deal though when it spools like a vf.

Last edited by Concillian; 10-12-2013 at 01:27 AM.
Concillian is offline   Reply With Quote
Old 10-12-2013, 10:08 AM   #547
LittleBlueGT
Scooby Specialist
 
Member#: 96204
Join Date: Sep 2005
Chapter/Region: W. Canada
Location: Winnipeg
Vehicle:
2013 STI GR
White

Default

Quote:
Originally Posted by Concillian View Post
No twin scroll for the small frames. Don't know that it's a big deal though when it spools like a vf.
Most of the OEMs (like BMW) do TS on much smaller turbos. So I believe that a TS 6758 (if it existed) would see benefits yet.

Everytime I plot it out on matchbot it is nowhere near the surge line, so if it responded a little bit faster in TS, I don't think there would be any complainers.

I would have bought in TS if it existed.
LittleBlueGT is offline   Reply With Quote
Old 10-12-2013, 02:19 PM   #548
subydude
Scooby Specialist
 
Member#: 80649
Join Date: Jan 2005
Chapter/Region: South East
Location: Columbia, SC
Vehicle:
2000 2.5 Auto-X RSTi
What's A Head Gasket?

Default

So when will this actually be available?
subydude is offline   Reply With Quote
Old 10-12-2013, 06:33 PM   #549
Concillian
Scooby Guru
 
Member#: 4414
Join Date: Feb 2001
Location: Dublin, CA
Vehicle:
2002 WRX Sedan
Midnight Black

Default

Here's what Geoff last said about 7163 availability:
Quote:
7163 production is going on through october. We are not going to list them on our site until the reservation lists are filled, too many phone calls about them as it is. people on our reservation lists will be getting the turbos first, thanks everyone for your patience still a few weeks away but its happening. I will ask if i can post a couple photos
Concillian is offline   Reply With Quote
Old 10-12-2013, 09:39 PM   #550
Leafy
Scooby Specialist
 
Member#: 330625
Join Date: Aug 2012
Chapter/Region: NESIC
Location: MA
Vehicle:
2006 WRX
WRB

Default

At some point they're going to make a B1 framed TS turbine housing.

Also you cant just wack the stock flange off that 1.5scroll header and weld on a t25 flange. The EFR is a lot longer than a mitsu turbo so I highly doubt it would fit like that. I think your best bet to use most of your header is to go rotated with the 7064 and TS turbine manifold. That should hit 400 on 93 without even trying and still spool pretty well. Though the 6758 with any header that takes a stock flange up pipe would probably be better.
Leafy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 12:50 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.