Slower spool with EWG
Results 1 to 10 of 10

This is a discussion on Slower spool with EWG within the Engine Modifications forums, part of the Tech & Modifying & General Repairs category; Hey guys so I just finished installing my grimmspeed tial 38mm ewg kit, Ive been working on my tune with ...

  1. #1
    Registered User Dgmftw's Avatar
    Join Date
    Sep 2012
    Location
    Ormond Beach
    Posts
    53

    Slower spool with EWG

    Hey guys so I just finished installing my grimmspeed tial 38mm ewg kit, Ive been working on my tune with torqued performance, I swear it feels like I have noticeably more lag with the ewg setup, I used fresh gaskets everywhere and torqued down everything good and proper, I believe I also have the V bands on correctly for the WG, One question I have is the air fittings on the WG do you guys use thread tape? I noticed it was a banjo bolt style with 2 washers so I did not use any additional tape, I also used loctite on the plugs for the EWG.

    Anyhow here is a picture of its installed as well as a video of a test run on low boost.
    Click image for larger version. 

Name:	Grimmspeed-EBCS+EWG.gif 
Views:	47 
Size:	8.3 KB 
ID:	111160
    Click image for larger version. 

Name:	22097_10151197246827051_10479455_n.jpg 
Views:	47 
Size:	99.1 KB 
ID:	111159
    2013 WRX EWG - YouTube

  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #2
    Master Baiter EJ257's Avatar
    Join Date
    Aug 2007
    Location
    On a stream bank somewhere
    Posts
    19,670
    I Support ClubWRX
    You have before/after logs?
    2005 WRX STi (Mods | Virtual Dyno)

    Resident Tuner @ WTF Tuning, LLC

    "Never trust anything that bleeds for a week and lives ..."

    UNYSOC

  4. #3
    Registered User Dgmftw's Avatar
    Join Date
    Sep 2012
    Location
    Ormond Beach
    Posts
    53

  5. #4
    Master Baiter EJ257's Avatar
    Join Date
    Aug 2007
    Location
    On a stream bank somewhere
    Posts
    19,670
    I Support ClubWRX
    According to your logs...
    Before (3218 RPMs): 15.96PSI
    After (3218 RPMs): 17.99PSI

    So, how is that slower spool?

    You have higher boost in the before log, but you're flowing more air (g/s) in the after log.
    2005 WRX STi (Mods | Virtual Dyno)

    Resident Tuner @ WTF Tuning, LLC

    "Never trust anything that bleeds for a week and lives ..."

    UNYSOC

  6. #5
    Registered User Heide264's Avatar
    Join Date
    May 2010
    Location
    Pittsburgh, PA
    Posts
    4,168
    I Support ClubWRX

    Re: Slower spool with EWG

    You used both the top and bottom of the diaphragm as well. That allows better boost modulation at the cost of less "mechanical control".

    It's analogous to using an interrupt based boost controller. It is very tedious to tune an ebcs to achieve mechanical spool. You can get it quite close though depending on time invested. Normally what happens is that you keep the ebcs at a very high duty cycle (as if it were mechanical) until you hit target boost.. At which point it opens a lot and acts more like a bleed type ebcs. The issue is that it isn't easy to do smoothly.

    I don't have experience tuning my ewg with both top and bottom lines, so I can't say for certain. Nor did I dig through the logs. Try to figure out if your ewg is opening partially before full boost. If so, you need to up the duty cycle until you want it to open (similar to the ebcs).

    What spring pressure do you have the ewg at?

    Will check out the logs when I get to a computer most likely tomorrow.
    Quote Originally Posted by Trainrex
    He was throwing balloons filled with sulfuric acid and shrapnel at the swat team. They finally had to take him down with rubber bullets.
    2011 STi Build Log
    -Part 1 - Reading, Data Logging, and Analyzing Data
    -Part 2 - Turbocharger 101 & Basic Boost Control
    -Part 3 - EcuFlash, Experimental Defintions, and a Drive By Wire Intro

  7. #6
    zax
    zax is offline
    \_(ツ)_/ zax's Avatar
    Join Date
    Nov 2008
    Location
    Neverland Ranch, Maryland
    Posts
    12,680
    I Support ClubWRX I Support ClubWRX
    Here is the situation that is typical with EWG setups: Actual Spool vs. Perceived Spool. My buddy and I upgraded our turbos at the same time, but went with different routes. My buddy had gone VF39 on the EJ205 with an EWG and STi TMIC --- 287whp tuned at 20 PSI. I had gone slightly bigger with an TD05-18G on an EJ205, IWG, STi TMIC -- 303whp tuned at 20.5 PSI with peak boost arriving at 3700rpm in 3rd gear.

    Now, we had the opportunity to test drive each others' cars. Immediately after driving my car, he exclaimed "your turbo spools faster than mine!" Thinking to myself, "that's impossible," I test drove his car and came to the same conclusion. Now, we performed a datalog on his car vs. mine and indeed my car hit 20.5 PSI by approx. 3600-3700 RPM and he was hitting 20 PSI by 3200 RPM in 3rd gear. What we discovered is that the act of the EWG opening (the sound produced) causes the mind to perceive the "turbo spooling" differently than the IWG.

    It is likely that what you've experienced is precisely the same as what we documented.
    2015 CWP WRX STi ... But how did I get roped back into an EJ motor?!
    Zax's utterly unimaginably stock 2015 STi build thread
    Zax's Shaggin' Wagon Build Thread Now tuned for 99% pure Unicorn Jizz!

    Zach | Moderator -- Mid-Atlantic States, Tech & Modifying & General Repairs
    Rollin' with the Bugeye Mafia #302 | N.E.R.D. Subject Zero
    Facebook me here

    Your Mid-A local board: http://www.clubwrx.net/forums/mid-atlantic-states/

  8. #7
    Registered User Heide264's Avatar
    Join Date
    May 2010
    Location
    Pittsburgh, PA
    Posts
    4,168
    I Support ClubWRX

    Re: Slower spool with EWG

    Or your turbo was flowing more than his at a given pressure during spool up. I wouldn't be surprised.

    When I added the ewg I felt the opposite. It spooled like you were running into a wall I thought. With the headers and other stuff, it's difficult to compare verbatim.

    I guess at first the sound could be misleading. Especially if you don't keep it shut until peak boost. Good point.

    The more I tune my car, the more I realize how important smooth boost control is. It's amazing how a boost spike (or lack there of) of only a psi or two can change the feel of the car. I think a smooth consistent boost curve is very underrated though, especially with some dyno tunes.
    Quote Originally Posted by Trainrex
    He was throwing balloons filled with sulfuric acid and shrapnel at the swat team. They finally had to take him down with rubber bullets.
    2011 STi Build Log
    -Part 1 - Reading, Data Logging, and Analyzing Data
    -Part 2 - Turbocharger 101 & Basic Boost Control
    -Part 3 - EcuFlash, Experimental Defintions, and a Drive By Wire Intro

  9. #8
    Registered User Dgmftw's Avatar
    Join Date
    Sep 2012
    Location
    Ormond Beach
    Posts
    53
    Quote Originally Posted by zax View Post
    It is likely that what you've experienced is precisely the same as what we documented.
    Definitely the sound can be really perceiving.

    Quote Originally Posted by Heide264 View Post
    Or your turbo was flowing more than his at a given pressure during spool up. I wouldn't be surprised.

    When I added the ewg I felt the opposite. It spooled like you were running into a wall I thought. With the headers and other stuff, it's difficult to compare verbatim.

    I guess at first the sound could be misleading. Especially if you don't keep it shut until peak boost. Good point.

    The more I tune my car, the more I realize how important smooth boost control is. It's amazing how a boost spike (or lack there of) of only a psi or two can change the feel of the car. I think a smooth consistent boost curve is very underrated though, especially with some dyno tunes.
    You make very valid points , the slightest oscillation of boost can be felt and quite noticeable.

    spring tension is set to .9 bar, I believe I can hear it start to open slightly before that
    Last edited by Dgmftw; 01-20-2013 at 12:44 PM.

  10. #9
    Registered User Heide264's Avatar
    Join Date
    May 2010
    Location
    Pittsburgh, PA
    Posts
    4,168
    I Support ClubWRX

    Re: Slower spool with EWG

    Okay. I'd have to go back and look at the ebcs stuff to figure out which port is which on the ebcs. I believe yours is configured to not open much before spring pressure (as you confirmed). Some run vacuum to that nipple to effectively lower spring tension.

    I will take a look at your logs and see tomorrow. I am leaning towards a tune issue personally but never know.
    Quote Originally Posted by Trainrex
    He was throwing balloons filled with sulfuric acid and shrapnel at the swat team. They finally had to take him down with rubber bullets.
    2011 STi Build Log
    -Part 1 - Reading, Data Logging, and Analyzing Data
    -Part 2 - Turbocharger 101 & Basic Boost Control
    -Part 3 - EcuFlash, Experimental Defintions, and a Drive By Wire Intro

  11. #10
    Master Baiter EJ257's Avatar
    Join Date
    Aug 2007
    Location
    On a stream bank somewhere
    Posts
    19,670
    I Support ClubWRX
    Quote Originally Posted by Heide264
    Okay. I'd have to go back and look at the ebcs stuff to figure out which port is which on the ebcs. I believe yours is configured to not open much before spring pressure (as you confirmed). Some run vacuum to that nipple to effectively lower spring tension.

    I will take a look at your logs and see tomorrow. I am leaning towards a tune issue personally but never know.
    There's a slight boost oscillation (that's something the tuner needs to address).

    Again, at the 3218 RPM level, you're flowing 20g/s more air with the EWG, which means it's more powerful. It may feel "slower", but in fact, it isn't.
    2005 WRX STi (Mods | Virtual Dyno)

    Resident Tuner @ WTF Tuning, LLC

    "Never trust anything that bleeds for a week and lives ..."

    UNYSOC

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •