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Star Performance Testing Day – Pt4 N75s

Ess_Three Feb 19, 2004

  1. JamS3

    JamS3 Active Member

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    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.
     
  2. Prawn

    Prawn My other car is a MINI!!!!

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    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!
     
  3. Stewart

    Stewart Member

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    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.
     
  4. dubbers

    dubbers Motown UK

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    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.
     
  5. Daniel Vzla

    Daniel Vzla Member

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    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?
     
  6. Ess_Three

    Ess_Three Active Member

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    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...
     
  7. AndybS3

    AndybS3 Member

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    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
     
  8. Ess_Three

    Ess_Three Active Member

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    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.
     
  9. scib4

    scib4 Beep-Beep!

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    AndyB, where you up at Knockhill on Saturday in the 340R?

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

    AndybS3 Member

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    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
     
  11. dultanur

    dultanur all promises, no action :)

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    can't help it...i love your car mate!!! next time you take a drive give it one for me...
     
  12. Ess_Three

    Ess_Three Active Member

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    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.
     
  13. AndybS3

    AndybS3 Member

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    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
     
  14. Fandango80

    Fandango80 Member

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    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!
     
  15. Bellic

    Bellic Member

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    if you switch the ignition back off and on usually resets the limp mode
     
  16. Dani_B19

    Dani_B19 Audi-sports own special child.

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    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?
     
  17. scib4

    scib4 Beep-Beep!

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    Blast from the past..........
     
  18. Shy19s

    Shy19s Oil running through my veins.

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    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!
     
  19. larsmate

    larsmate Member

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    Clear the fault code with VAG-COM.
     
  20. Dani_B19

    Dani_B19 Audi-sports own special child.

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    What do you do if you havent got vag com? Are you sh*ted!
     
  21. jojo

    jojo Looking for Boost! Staff Member Moderator Team Daytona Audi S3 quattro Audi A6 Audi Avant Owner Group

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    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.
     
  22. Dani_B19

    Dani_B19 Audi-sports own special child.

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    Thanks jojo, thats all i needed to know, didnt want the car togo into limp mode an leave me up sh*t creak
     
  23. vetch

    vetch S3

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    That question has been asked many, many times, and to my knowledge, no one has actually answered it properly. Nice one Jojo:icon_thumright:
     
  24. Westy

    Westy Well-Known Member

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    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.
     
  25. jojo

    jojo Looking for Boost! Staff Member Moderator Team Daytona Audi S3 quattro Audi A6 Audi Avant Owner Group

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    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.
     
  26. S3 Rav

    S3 Rav Well-Known Member

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    so does this happend with everyone with the n75 valve?
     
  27. vetch

    vetch S3

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    Not so much on the APY S3s apparently. Ive read this on more than one occasion, but it could be hearsay.
     
  28. Dani_B19

    Dani_B19 Audi-sports own special child.

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    Your right vetch, its been asked acouple of times in this post and no one answered it, cheers jojo
     
  29. s3_kev

    s3_kev Stage2'd!!!!!!

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    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
     
  30. fran-s3

    fran-s3 Active Member VCDS Map User

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    Happened with my 01 AMK engine when I fitted the J.
     
  31. S3 Rav

    S3 Rav Well-Known Member

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    thats what i was wondering fran? i've got an amk too so wanted to know what peoples experiences were
     
  32. s3gazz

    s3gazz Well-Known Member

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    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
     
  33. <tuffty/>

    <tuffty/> Badger 5 Edition...Its all about the flow... Staff Member Moderator Audi S3

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    Std F valve

    <tuffty/>
     
  34. s3gazz

    s3gazz Well-Known Member

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    ok cheers ill keep that then tuffty
     
  35. cecilthesausage

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

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    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
     
  36. s3gazz

    s3gazz Well-Known Member

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    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
     

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