Duty cycle
Page 1 of 2 12 LastLast
Results 1 to 15 of 29

This is a discussion on Duty cycle within the General Maintenance, Troubleshooting & Accidents. forums, part of the Tech & Modifying & General Repairs category; I have a '12 wrx, where should the injector duty cycle be? On average modded or unmodded?...

  1. #1
    Registered User SubiEj255's Avatar
    Join Date
    Jul 2012
    Location
    Baltimore
    Posts
    387

    Duty cycle

    I have a '12 wrx, where should the injector duty cycle be? On average modded or unmodded?
    A car is only as good as its driver

  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #2
    UnBanned Sinister's Avatar
    Join Date
    Nov 2006
    Location
    Denver Metro Area
    Posts
    17,628
    I Support ClubWRX
    under 90% is recommended
    Kevin
    Moderator
    Sinister's Blowoff Valve FAQ
    WRX Gas Mileage FAQ
    Sinister's Progress Thread - 430whp 429wtq - Sold
    Firearms Enthusiasts Thread

    The Sheriff's Star at the bottom left corner rates a user's reputation.
    If you found a user's post to be helpful or quite the opposite, please make it known to them by clicking the Star!

  4. #3
    Registered User SubiEj255's Avatar
    Join Date
    Jul 2012
    Location
    Baltimore
    Posts
    387
    Yea I figured that. I pulled logs my IDCs are 98%. This is with the Cobb stage 1 91 tune, while using 93 octane.
    A car is only as good as its driver

  5. #4
    Admiral Ackbar the 1st mycologist's Avatar
    Join Date
    Oct 2005
    Location
    Late Devonian
    Posts
    13,214
    I Support ClubWRX
    How much boost are you hitting?
    "From a little spark may burst a mighty flame." - Dante
    "The stitch is lost unless the thread is knotted." - Italian proverb

  6. #5
    Registered User Ruh Roh's Avatar
    Join Date
    Dec 2011
    Location
    Pottstown PA
    Posts
    3,258
    98% on a stage 1 tune! wow didnt think it'd be that much. And why arent u using the 93 octane tune if your using 93..?

  7. #6
    Registered User SubiEj255's Avatar
    Join Date
    Jul 2012
    Location
    Baltimore
    Posts
    387
    This is by 7k redline. Peak boost is 16.8 or something like that. I don't have the exact numbers in front of me right now. It wasn't higher than 16.8, I do know that. I'm using 91 tune b/c I wanted to use that extra octane as an buffer to "richen" the car up. I k ow these cars run lean, so I wanted to have a small window.
    A car is only as good as its driver

  8. #7
    and the Funky Bunch Calvinball's Avatar
    Join Date
    Jan 2012
    Location
    Philly Area
    Posts
    5,970
    Quote Originally Posted by SubiEj255 View Post
    This is by 7k redline. Peak boost is 16.8 or something like that. I don't have the exact numbers in front of me right now. It wasn't higher than 16.8, I do know that. I'm using 91 tune b/c I wanted to use that extra octane as an buffer to "richen" the car up. I k ow these cars run lean, so I wanted to have a small window.
    Someone with more experience in tuning can correct me if I'm wrong, but I'm fairly sure that octane rating is not going to affect your A/F ratio, or as you put it "richen the car up."
    - Will
    First Mods: What to do and what not to do
    Current Car: 2014 Golf TDI
    Previous Cars:2012 WRB WRX Hatch, 2004 RSX-S, 1998 Grand Prix GTP
    "Isn't it amazing how smart you feel when you just aren't being stupid?"

  9. #8
    Admiral Ackbar the 1st mycologist's Avatar
    Join Date
    Oct 2005
    Location
    Late Devonian
    Posts
    13,214
    I Support ClubWRX
    Quote Originally Posted by Calvinball View Post
    Someone with more experience in tuning can correct me if I'm wrong, but I'm fairly sure that octane rating is not going to affect your A/F ratio, or as you put it "richen the car up."
    Correct, the octane of the gas won't directly but the map will probably give a buffer against knock. I'm not sure how Cobb does it, but the 91 octane map probably uses less timing or a richer mixture to keep the 91 octane gas from knocking. I'd run the 93 map and see for yourself if there is a knock issue or not.
    "From a little spark may burst a mighty flame." - Dante
    "The stitch is lost unless the thread is knotted." - Italian proverb

  10. #9
    and the Funky Bunch Calvinball's Avatar
    Join Date
    Jan 2012
    Location
    Philly Area
    Posts
    5,970
    Quote Originally Posted by mycologist View Post
    Correct, the octane of the gas won't directly but the map will probably give a buffer against knock. I'm not sure how Cobb does it, but the 91 octane map probably uses less timing or a richer mixture to keep the 91 octane gas from knocking. I'd run the 93 map and see for yourself if there is a knock issue or not.
    Yeah, I just re-read that post and realized I may have interpreted what the OP wrote incorrectly. The 91 tune might possibly be richer for safety. However, I believe that using 93 gas on a 91 tune is not going to help with anything unless for some reason 91 gas was knocking on the 91 tune, correct?
    - Will
    First Mods: What to do and what not to do
    Current Car: 2014 Golf TDI
    Previous Cars:2012 WRB WRX Hatch, 2004 RSX-S, 1998 Grand Prix GTP
    "Isn't it amazing how smart you feel when you just aren't being stupid?"

  11. #10
    Registered User SubiEj255's Avatar
    Join Date
    Jul 2012
    Location
    Baltimore
    Posts
    387
    I pulled logs for both tunes. Knock isn't the issue in either tune. Ill post both with I get to my computer, but the question was the duty cycle of the injectors; why are they almost maxed out? Is this normal? What are the size of the stock injectors?
    A car is only as good as its driver

  12. #11
    Admiral Ackbar the 1st mycologist's Avatar
    Join Date
    Oct 2005
    Location
    Late Devonian
    Posts
    13,214
    I Support ClubWRX
    It doesn't seem normal to me - it is too high.

    Was the duty cycle lower with the 93 map? If it is a leaner map....
    "From a little spark may burst a mighty flame." - Dante
    "The stitch is lost unless the thread is knotted." - Italian proverb

  13. #12
    and the Funky Bunch Calvinball's Avatar
    Join Date
    Jan 2012
    Location
    Philly Area
    Posts
    5,970
    Quote Originally Posted by SubiEj255 View Post
    I pulled logs for both tunes. Knock isn't the issue in either tune. Ill post both with I get to my computer, but the question was the duty cycle of the injectors; why are they almost maxed out? Is this normal? What are the size of the stock injectors?
    If there was no knock when running the 93 tune, and you use 93 gas, you should just run the 93 tune. If you are concerned that it might lean the car out too much, contact Cobb and ask them how the a/f ratios differ between the 91 and 93 tunes. Or save some money and just buy 91 gas for the 91 tune. Running 93 octane gives no additional benefit if you are on the 91 tune with no knock issues.

    To your questions: All you have is a stage 1 tune, no other mods? If so, that seems not normal. Stock injector size is 565 I believe.
    - Will
    First Mods: What to do and what not to do
    Current Car: 2014 Golf TDI
    Previous Cars:2012 WRB WRX Hatch, 2004 RSX-S, 1998 Grand Prix GTP
    "Isn't it amazing how smart you feel when you just aren't being stupid?"

  14. #13
    Admiral Ackbar the 1st mycologist's Avatar
    Join Date
    Oct 2005
    Location
    Late Devonian
    Posts
    13,214
    I Support ClubWRX
    16.8 psi seems high for a stage I tune, but I think that may be normal for the new maps.

    The injectors should be <90 on a stage II map, so there is something funny going on for sure.
    "From a little spark may burst a mighty flame." - Dante
    "The stitch is lost unless the thread is knotted." - Italian proverb

  15. #14
    zax
    zax is offline
    \_(ツ)_/ zax's Avatar
    Join Date
    Nov 2008
    Location
    Neverland Ranch, Maryland
    Posts
    13,156
    I Support ClubWRX I Support ClubWRX
    Unfortunately, the new ATR won't allow me to view the 2012 maps, but classically, Cobb has traded very rich fueling for added timing.
    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/

  16. #15
    Moderator Donkey's Avatar
    Join Date
    Apr 2005
    Location
    Da boonies
    Posts
    6,149
    I Support ClubWRX
    Quote Originally Posted by mycologist View Post
    It doesn't seem normal to me - it is too high.

    Was the duty cycle lower with the 93 map? If it is a leaner map....
    This. Use the 93 map. The 91 is richer. Plus OTS maps will run rich. I would see about getting a custom tune. Also colder weather = higher duty cycles.
    Resident Adviser @ WTF Tuning, LLC
    2002 FORESTER S
    1998 FORESTER S




Page 1 of 2 12 LastLast

Posting Permissions

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