1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Star Performance Testing Day – Pt4 N75s

Discussion in 'A3/S3 Forum (8L Chassis)' started by Ess_Three, Feb 19, 2004.

  1. JamS3
    Offline

    JamS3 Active Member

    Joined:
    Jun 17, 2003
    Messages:
    2,257
    Likes Received:
    14
    [Mar 10, 2007]
    Prawn

    There is no point fitting a J valve after a remap when you haven't had it done yet. You may aswell get a custom remap and speak with the tuner to incorporate the gain your J valve would have given.
    #41
  2. Prawn
    Offline

    Prawn My other car is a MINI!!!!

    Joined:
    Dec 8, 2006
    Messages:
    9,815
    Likes Received:
    1,513
    [Mar 10, 2007]
    interesting. i was under the impression that if a car is mapped with the J valve in place, it will give exactly the same boost as if it were mapped with the standard valve. thus the remap would totally negate the increased boost of the J-valve.

    im sure there were a few threads on this when i joined back in november. many people saying fitting the J valve before a remap was pointless, as the remap would work around the increased boost of the N75 to deliver the boost the map was inteneded to run.

    sorry if that sounds a little confused, it makes sense to me, sort of!
    #42
  3. Stewart
    Offline

    Stewart Member

    Joined:
    Feb 17, 2005
    Messages:
    705
    Likes Received:
    8
    [Mar 10, 2007]
    Yes you're right which is what Jam was saying :)

    Mike at Jabba told me this personally, he preferred the C valve as fitted to early ECU's (non drive by wire) as it helped with a flatter torque curve...

    Fitting the J valve post map DID make a difference but I was overboosting and hitting limp.
    #43
  4. dubbers
    Offline

    dubbers Motown UK

    Joined:
    Feb 18, 2007
    Messages:
    17
    Likes Received:
    0
    [Mar 12, 2007]
    I ran the 'J' in a remapped BAM engined TTR for most of the summer last year. My experience was that it was fine (and made the portly TT quite savage), until about November or so when it kept going into limp... Vagcom reports
    and occasionally accompanied with
    In my situation the car effectively became boostless. To resolve was a few seconds with VagCom to reset. Since then I've swapped back to the standard N75.
    #44
  5. Daniel Vzla
    Offline

    Daniel Vzla Member

    Joined:
    Dec 28, 2006
    Messages:
    84
    Likes Received:
    0
    [Mar 12, 2007]
    Ok so summarizing, all the engines but the AGU go into Limp with this mod? a N75 J in a chipped AGU will make any difference?
    #45
  6. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    7
    [Mar 12, 2007]
    Exactly my experiences...although it was safe for the engine for me to run an alternative N75, it made the power delivery very savage...and kept hitting limp mode.

    I too had to reach for VAG Com to get any boost back...
    #46
  7. AndybS3
    Offline

    AndybS3 Member

    Joined:
    Jun 8, 2003
    Messages:
    233
    Likes Received:
    0
    [Mar 13, 2007]
    I found the J valve a lot more aggressive on boost and initially would hit limp mode but as you get used to it there was a way of driving round it.

    It also helps if you have APR software with fault code reset as it's just a matter of dipping the clutch and running through the reset feature after hitting limp
    #47
  8. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    7
    [Mar 13, 2007]
    On mine, with the J valve fitted, it would hit limp if you drove at small throttle openings and let the boost build slowly...if you dropped a gear and mashed the throttle open wide, you were safe.
    Fine on back roads...not so good on Motorways.
    #48
  9. scib4
    Offline

    scib4 Beep-Beep!

    Joined:
    Dec 6, 2006
    Messages:
    272
    Likes Received:
    1
    [Mar 13, 2007]
    AndyB, where you up at Knockhill on Saturday in the 340R?

    There can't be many of them in Scotland!
    #49
  10. AndybS3
    Offline

    AndybS3 Member

    Joined:
    Jun 8, 2003
    Messages:
    233
    Likes Received:
    0
    [Mar 13, 2007]
    Exactly the same here Glen.


    Wasn't me at Knockhill mate, still too chilly yet for my liking, seemingly there's about 6 340's in Scotland 3 or 4 of them in Aberdeen
    #50
  11. dultanur
    Offline

    dultanur all promises, no action :)

    Joined:
    Sep 17, 2006
    Messages:
    407
    Likes Received:
    0
    [Mar 13, 2007]
    can't help it...i love your car mate!!! next time you take a drive give it one for me...
    #51
  12. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    7
    [Mar 13, 2007]
    Really?
    Never seen any about...

    I know a lad with an Atom...but don't know of any 340 owners.

    In saying that...there are a lot of rare and expensive cars 'hidden' in Aberdeen...more so than most people think.
    #52
  13. AndybS3
    Offline

    AndybS3 Member

    Joined:
    Jun 8, 2003
    Messages:
    233
    Likes Received:
    0
    [Mar 14, 2007]
    I was talking to another Scot on one of the Lotus forums from Aberdeen Glen who had one and he mentioned there were 3 or 4 up there.

    They really are for the track alone and good weather, most if not all will be tucked up in a garage until Summer
    #53
  14. Fandango80
    Offline

    Fandango80 Member

    Joined:
    Oct 15, 2004
    Messages:
    71
    Likes Received:
    0
    [Dec 21, 2007]
    Guys this looks like something id like to try but im concerned about limp mode... if my a3 hits limp mode, will it last just a few mins or will it stay in this mode until it is physically reset with vag com?

    Cheers for all the interesting posts on this one lads!
    #54
  15. Bellic
    Offline

    Bellic Member

    Joined:
    Dec 19, 2006
    Messages:
    265
    Likes Received:
    0
    [Dec 22, 2007]
    if you switch the ignition back off and on usually resets the limp mode
    #55
  16. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,285
    Likes Received:
    90
    [May 18, 2009]
    Thinking about doing this but can someone give a clear answer, how do you get rid of limp mode if your car goes into it?
    #56
  17. scib4
    Offline

    scib4 Beep-Beep!

    Joined:
    Dec 6, 2006
    Messages:
    272
    Likes Received:
    1
    [May 18, 2009]
    Blast from the past..........
    #57
  18. Shy19s
    Offline

    Shy19s Oil running through my veins.

    Joined:
    Apr 9, 2008
    Messages:
    886
    Likes Received:
    0
    [May 19, 2009]
    I miss reading techinical stuff like this... Hopefully matt will give a detailed report on what his car is running so we can all have a very interesting read!
    #58
  19. larsmate
    Offline

    larsmate Member

    Joined:
    Apr 14, 2004
    Messages:
    121
    Likes Received:
    5
    [May 19, 2009]
    Clear the fault code with VAG-COM.
    #59
  20. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,285
    Likes Received:
    90
    [May 19, 2009]
    What do you do if you havent got vag com? Are you sh*ted!
    #60
  21. jojo
    Offline

    jojo Looking for Boost! Staff Member Moderator

    Joined:
    Sep 4, 2003
    Messages:
    26,608
    Likes Received:
    1,965
    [May 19, 2009]
    Nono, if your car goes into 'limp home' mode, all you need to do is switch the car off and then back on, and it will be back to normal.
    It's will probably log a DTC which will com up in a Vagcom scan, nothing to worry about unless you have actually broken something.
    #61
  22. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,285
    Likes Received:
    90
    [May 19, 2009]
    Thanks jojo, thats all i needed to know, didnt want the car togo into limp mode an leave me up sh*t creak
    #62
  23. vetch
    Offline

    vetch S3

    Joined:
    Apr 8, 2009
    Messages:
    430
    Likes Received:
    0
    [May 19, 2009]
    That question has been asked many, many times, and to my knowledge, no one has actually answered it properly. Nice one Jojo:icon_thumright:
    #63
  24. Westy
    Offline

    Westy Double Dark Side! Diesel & 8P

    Joined:
    Dec 2, 2008
    Messages:
    17,343
    Likes Received:
    988
    [May 19, 2009]
    The thing is, if you do the N75 valve mod and it puts your car into limp mode and you reset it by turning off and on again, limp mode will come straight back again unless you revert the valve mod back to standard again.
    #64
  25. jojo
    Offline

    jojo Looking for Boost! Staff Member Moderator

    Joined:
    Sep 4, 2003
    Messages:
    26,608
    Likes Received:
    1,965
    [May 19, 2009]
    It will go back into 'Limp home' mode after a reset if you decide to drive it like a loon again straight after you restart it. It usually only goes into limp mode when the ECU detects a boost spike or something similar, which is what the changing of the N75 does to trick the car into a wallop of torque, though I stand to be corrected.
    #65
  26. S3 Rav
    Offline

    S3 Rav Well-Known Member

    Joined:
    Feb 13, 2008
    Messages:
    2,826
    Likes Received:
    27
    [May 19, 2009]
    so does this happend with everyone with the n75 valve?
    #66
  27. vetch
    Offline

    vetch S3

    Joined:
    Apr 8, 2009
    Messages:
    430
    Likes Received:
    0
    [May 19, 2009]
    Not so much on the APY S3s apparently. Ive read this on more than one occasion, but it could be hearsay.
    #67
  28. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,285
    Likes Received:
    90
    [May 19, 2009]
    Your right vetch, its been asked acouple of times in this post and no one answered it, cheers jojo
    #68
  29. s3_kev
    Offline

    s3_kev Stage2'd!!!!!!

    Joined:
    Feb 17, 2008
    Messages:
    1,998
    Likes Received:
    18
    [May 19, 2009]
    my apy is fine been runing mine for some time i had to bypass my n249 valve though for it to run smother but think it was because the valve was knackered more then because i had the 75j fitted
    #69
  30. fran-s3
    Offline

    fran-s3 Active Member VCDS Map User

    Joined:
    Jan 29, 2008
    Messages:
    1,103
    Likes Received:
    1
    [May 19, 2009]
    Happened with my 01 AMK engine when I fitted the J.
    #70
  31. S3 Rav
    Offline

    S3 Rav Well-Known Member

    Joined:
    Feb 13, 2008
    Messages:
    2,826
    Likes Received:
    27
    [May 20, 2009]
    thats what i was wondering fran? i've got an amk too so wanted to know what peoples experiences were
    #71
  32. s3gazz
    Offline

    s3gazz Well-Known Member

    Joined:
    Aug 11, 2010
    Messages:
    1,264
    Likes Received:
    64
    [Feb 19, 2011]
    hi just wondering what would be the best n75 for my amk 210 s3 as i dont have a clue with everything iv been told is dif wih them on dif engine modules just think its on its way out thats all tar
    #72
  33. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    16,314
    Likes Received:
    1,492
    [Feb 19, 2011]
    Std F valve

    <tuffty/>
    #73
  34. s3gazz
    Offline

    s3gazz Well-Known Member

    Joined:
    Aug 11, 2010
    Messages:
    1,264
    Likes Received:
    64
    [Feb 19, 2011]
    ok cheers ill keep that then tuffty
    #74
  35. cecilthesausage
    Offline

    cecilthesausage ...It's Never Finished...

    Joined:
    Jul 20, 2010
    Messages:
    933
    Likes Received:
    111
    [Feb 19, 2011]
    I have gone from standard F valve to J Valve over the last few days with an APY engine code. (Let it be known that I was told not to but when your as green as grass you like to try all the options what everybody else has already tried but dont listen to what people say lol, a bit like my 18 year old son lol) I fitted it the wrong way round to start with and hit limp mode 2wice in half an hour and then fitted it right way round and everything was hunky dory could notice a real change but then the sh@t hit the fan and hopefully i dont have big problems I will start a thread 2morrow to find out
    #75
  36. s3gazz
    Offline

    s3gazz Well-Known Member

    Joined:
    Aug 11, 2010
    Messages:
    1,264
    Likes Received:
    64
    [Feb 20, 2011]
    tar mate hope all goes well for ya i hit limp mode at 20psi with the standered f valve on my amk so god nose what it would be like with the j valve
    #76

Share This Page