Stock power, auto engine vs manual

Discussion in 'Technical' started by A-Bris-Z, Jul 23, 2013.

  1. Z32 TT

    Z32 TT Active Member

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    if it was me:

    1.check spark plugs/base timing
    2.check fuel pressure is ok (logged against boost) and AFR and timing aswell
    3.replace injectors with flowed known set


    see how that goes.
     
  2. A-Bris-Z

    A-Bris-Z Carcraze

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    From what I hear you should expect 230-250 at 14-15psi. Let us know how you go.
     
  3. MagicMike

    MagicMike Moderator Staff Member

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    No you should expect 220 to 230.
     
  4. GWZED

    GWZED 97 2+2 TT Targa

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    Ill let you both know. Getting tested at the hubs, so should get an accurate read
     
  5. A-Bris-Z

    A-Bris-Z Carcraze

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    Below is a copy one one of the runs. Dave cleaned up the line a bit and knocked out a few bumps with further runs, but ultimately wound the boost back a bit to keep it safe in the end. You can see where is started pinging towards the end of this run. Sorry didn't get any figures for injector duty or fuel pressure.

    Edit: I just noticed that's it's boosting well......hit 15psi at 3500rpm, and 10psi at 3000rpm.

    [​IMG]
     
  6. A-Bris-Z

    A-Bris-Z Carcraze

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    Good point, I'll have to confirm.
     
  7. A-Bris-Z

    A-Bris-Z Carcraze

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    Well if that's the case then it's not as bad as I thought. If I'm getting 200 and 220 is what is expected then the gap isn't major.
     
  8. MagicMike

    MagicMike Moderator Staff Member

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    Agree you arent far off the mark. A good tune will do wonders. A good tune takes longer than a couple runs on a dyno ;)

    what boost control do u have? Spike to 16 then drops off to 12?

    what is your exhaust setup? Cat condition?
     
  9. A-Bris-Z

    A-Bris-Z Carcraze

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    Has a manual boost controller (turbotech). Exhaust is old aftermarket 2.5 inch system......unsure of condition of cats, is there a way to test?
     
  10. rob260

    rob260 Administrator Staff Member

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    Buggered cats shouldn't case pinging... If its pinging regardless of AFR and with timing taken out at the ECU it is sounding more and more like a cam timing issue
     
  11. Shane001

    Shane001 Well-Known Member

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    Could also be a bad tank of fuel. Won't be the first time.

    What did you fill up with and where from?
     
  12. MagicMike

    MagicMike Moderator Staff Member

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    My thinking was more along the lines of excessive backpressure. R33k had similar issues recently.
     
  13. kakaboy

    kakaboy New Member

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    26psi on stock engine :eek: no surprise your pinging
     
  14. Chilledpain

    Chilledpain Z Reaper

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    Just a question. Are u running one of those non genuine "replacement" afms? How was your afr? Running an aftermarket fuel pressure regulator?
     
  15. A-Bris-Z

    A-Bris-Z Carcraze

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    No, just a stock AFM and FPR. I have a wide band sensor so will try to get a look at what it's doing. Problem is at 5000rpm and 14psi I'm not inclined to look at the gauge for too long.

    Thanks for all of your thoughts, it looks like my two targets are cams and cats.
     
  16. A-Bris-Z

    A-Bris-Z Carcraze

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    Do you know if its a big job to have this checked Rob?
     
  17. zedboy

    zedboy Active Member

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    Its just a matter of getting your plastic timing belt cover off and checking it's all lined up correctly.

    Also is it possible that you may have had a fair amout of meat taken of the deck of the block and the heads causing a raise in comp ratio and possibly leading to detonation/pinging???

    Also a blocked up exhaust can cause det.

     
  18. Shane001

    Shane001 Well-Known Member

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    lol, look again :p
     
  19. Shane001

    Shane001 Well-Known Member

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    If you have Nistune can't you connect this up and then log it, along with lot's of other useful info, ie duty cycle?
     
  20. rob260

    rob260 Administrator Staff Member

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    Can also check with a timing wheel but yeah at the very least covers off and check the belt. Probably check base timing with a timing light first though.

    How does blocked exhaust cause pinging Matt? Higher combustion temps?
     

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