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Nitrous question...

Discussion in 'Nitrous Oxide (NOS)' started by JdmTc, Sep 21, 2007.

  1. StreetBrawler89
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    StreetBrawler89 Member

    Joined:
    Nov 20, 2008


    :loool::loool:
     
  2. turbo-tc
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    turbo-tc Member

    Joined:
    Feb 15, 2009
    Location:
    08/scion/tc
    well i have a question.
    i want to run a 75 shot on my turboed tc.
    is this okay to do?
    im running just the aem fic piggy back system
    im about to install my walbro 255.
    i have 550cc injectors on as well.
    i dont know what plugs to put on the car
    either, 1-3 stage colder. i dont know much about engines at all
    i just want my car to run safely and efficiently
     
  3. bdis3
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    bdis3 Member

    Joined:
    Jan 20, 2008
    Location:
    2008 Scion tC
    what psi are you running?
    auto or manual?
    hp?
    kit?
     
  4. turbo-tc
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    turbo-tc Member

    Joined:
    Feb 15, 2009
    Location:
    08/scion/tc
    8.5psi
    manual
    250-270hp
    never got dynoed.
    street tuned.
    and i have the dezod kit
    i have nst pulleys as well
     
  5. bdis3
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    bdis3 Member

    Joined:
    Jan 20, 2008
    Location:
    2008 Scion tC
    I would run colder plugs, and a 50 wet shot.

    Or

    You could always run the jets to the front of your intercooler and spray the crap out of that thing

    You might want to upgrade your clutch too
     
  6. turbo-tc
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    turbo-tc Member

    Joined:
    Feb 15, 2009
    Location:
    08/scion/tc
    im just looking to squeeze 300-325hp off my stock motor
    safely.
    i have the stage 1 act clutch.
    is that safe to assume i dont need a new clutch
    with the hp i want?


    but im thinking on getting the nx express intercooler kit.
    and just use c02.
    Dezod Motorsports. NX Ntercooler System-5LB Bottle
     
  7. StreetBrawler89
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    StreetBrawler89 Member

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    Nov 20, 2008
    The stock motor will only handle up to about 300hp with boost, adding boost and spray and I would rebuild almost everything, at minimum go -3 plugs. Im over cautious anywas.
     
  8. turbo-tc
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    turbo-tc Member

    Joined:
    Feb 15, 2009
    Location:
    08/scion/tc
    do you run -3 plugs?
    i also heard going to cold on plugs could
    make them foul out.
    i was told -2 would be fine
     
  9. StreetBrawler89
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    StreetBrawler89 Member

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    Nov 20, 2008
    Like I said I am very overcautious, I generally dont like the spray for anything more than a cooling agent as sugessted by bdis3, Im not running FI or Nitrous at this time so I still have the stock plugs. The reason I suggested the -3 plugs was because if you run 8.5 of extra air in your engine, then you run nitrous(which burns hotter) it basically the same as adding boost.
     
  10. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc
    true true.
    im in a process of buying a meth kit
    as we speak. ill see how well that holds up on my engine.
    also i only have a .6 bar spring in my tial, am i able to still up boost?

    ps i heard the nx express intercooler kit just freezes the intercooler which
    promotes colder air flow which pushes more fuel in the engine. is this safer than running wet nitrous? im only trying to get an adittion 50-70hp with what i got.
     
  11. StreetBrawler89
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    StreetBrawler89 Member

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    Nov 20, 2008
    That addition of only 50-70 will push your engine past it limits, My advice to you is to by some safety parts with that money, IE a new head, some better valve springs, get a professional tune, a new transmission, maybe new driveshafts. That stage 1 clutch is only just barely an upgrade from stock, might as well buy up a stage 4 and a lightwieght flywheel since your goals are the 300hp club

    Also, the intercooler freezer is safer than running nitrous, but it condenses the air going into the actual piston chambers, thus putting more strain on the valvetrain which can cause valve float from all that air being in the chamber, valve float will ruin your day fast quick and in a hurry.
     
  12. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc


    okay cool thanks for the info!
    where could i get a better tranmission for my tc?
     
  13. StreetBrawler89
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    StreetBrawler89 Member

    Joined:
    Nov 20, 2008
    Here The ClutchMasters Stuff
    Flywheel-http://www.killertc.com/product.php?productid=16690
    Stage 3 Clutch Kit-http://www.killertc.com/product.php?productid=16692&cat=344&bestseller
    Stage 4Clutch Kit w/ Flywheel Option-http://www.clutchmasters.com/shop/?page=shop%2Fflypage&MakeID=32&FromYear=2005&MakeModelID=33479&AppID=18909

    Competition Clutch Hardware

    Stage 4 Clutch-http://customizemyscion.com/store/index.php?main_page=product_info&cPath=1_15&products_id=54

    (12lb)Lightwieght Flywheel-http://customizemyscion.com/store/index.php?main_page=product_info&cPath=1_15&products_id=48

    (9lb)Ultra Lightweight Flywheel-http://customizemyscion.com/store/index.php?main_page=product_info&cPath=1_15&products_id=49

    If you live in a very Hilly region go with the 12 pounder, if not the 9 will do you right.
     
  14. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc
    i already have a 9 lb flywheel on
    ill just upgrade the clutch later on when
    expansion on the engine goes into full affect
     
  15. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc
    also this is the clutch i currently have on it.

    ACT Street Clutch Kit-tC 05+ (34% clamp load increase, 341 ft/lbs of TQ)
     
  16. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc
    how bout my full engine/transsmission list.

    dezod t3/t4 turbo kit 50trim[8.5psi]
    aem fic
    apexi avcr boost controller
    nst pulleys
    550cc injectors
    9lb flywheel
    act clutch
    walbro 255 pump
    ignalls torque dampner
    b&m short throw
     
  17. navylife59
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    navylife59 Super Moderator Staff Member

    Joined:
    Mar 22, 2006
    Location:
    Emory, Texas or Gretna, LA
    Just a little correction here, valve float is caused by the valve springs inability to control the linear movement of the valve. Excessive RPMs cause harmonic vibrations to oscillate the valve springs. This oscillation cause the valve tip/lifter/rocker arm to loose contact with the camshaft lobe during and after maximum lift. The valve will begin to rotate which will induce distortion stresses on the valve that will make the valve face flutter. This happens regardless of F/I, Nitrous, or N/A application. Watch this video that really shows what is going on here. YouTube - Valve Float
     
  18. adi tC
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    adi tC New Member

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    Jan 6, 2009
    stats from 2008 say that the Scion tC is the second most pulled over car by police:banghead:. only being beat by the Hummer H3
     
  19. turbo-tc
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    turbo-tc Member

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    Feb 15, 2009
    Location:
    08/scion/tc
    so i forgot to add now that my car was tuned at 10 psi with 100% meth injection.
    pulled out 276/294 on the mustang dyno.
    my gf without me knowing, bought me the nx express intercooler kit for my bday a few days ago. im quite mad she did cause i really have no use for it but i guess imma try and get it hooked up and tuned with my set up maybe just lower boost and ill be fine..
     
  20. navylife59
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    navylife59 Super Moderator Staff Member

    Joined:
    Mar 22, 2006
    Location:
    Emory, Texas or Gretna, LA
    Me thinks that you need to upsize your injectors to support 300WHP reliably. You will be saturating your injectors if you try to overshoot this mark. Less fuel, means less power dictated by the ECM or detonation if you try to push it with the piggyback.

    550CC=52.38lb/hour injectors. Using a conservative BSFC of 0.6 it works out to be 279.36BHP at the flywheel with 80% injector duty cycle.

    Note: Any duty cycle over 80% is reaching near saturation of the injectors. That leaves no room for the ECM and/or piggyback to, in the presence of knock, to add more fuel to cool the combustion chamber and prevent hotspots on the piston head. All the ECM can do at this point is to pull back timing which might not be enough incurring engine damage.

    Calculating 300WHP x 12% (average drivetrain loss) = 336BHP
    Plugging the numbers into the equation and you will need 63lb/hr 660cc injectors at 80% to support 300WHP.

    Now, if you add a water/meth kit in the mix, this is going to change the BSFC and allow you to support slightly more HP with your 550cc injectors. What exactly it can support is not known w/o an accurate BSFC number. You offset the need for larger injectors by increasing your meth jet size or you can add a secondary injector (550cc/4 will get you to 660cc injector size) if your piggyback supports this. Now you have to look at the rest of your fueling system. Can the fuel rail, stock regulator, and fuel pump handle the required flow rate? You might start looking at converting to a return fuel system with an external, boost based, fuel regulator. No fuel rail kits available on the market yet (my fault, sorry) so your stuck with modifying your OEM one. The OEM fuel pump can't support this demand, so an upgrade is a must. Your 255lph Walbro pump can support up to 100.7lb/hr injectors (4) or 537.07BHP using our current calculations.

    3.8lph=1gph
    255lph/3.8lph=67.1gph​
    1 gallon of gasoline=6 pounds (std average)
    67.1gph=402.6lb/hr​
    402.6pph/4 (injectors)=100.7lb/hr injectors.

    ....So if we take your 550cc injectors and add a secondary 550cc injector, you will have a max (100% duty cycle) flow rate demand of 261.9lb/hr. This leaves you plenty of room on your Walbro pump for upgrades.

    Of course, this all means nothing if the ECM does not play nice with your piggyback. Might be time to upgrade to a stand alone.


    Reference Calculations: Injector Selection Guide
     

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