Das Treffen der Generationen

    Die Toyota Supra Community für alle Supra Generationen

    Toyota Supra A90

    Besitzer der fünften Generation des Toyota Supra sind begeistert, denn was Leistung und Fahrdynamik hat der neue Supra A90 alle Erwartungen übertroffen.

    Toyota Supra MKIV

    Bekannt aus dem Fast & Furious Film, kam im Juli 1993 die vierte und bisher letzte Generation des Toyota Supra auf den Markt. International wird dieser Typ "Supra MKIV" genannt.

    Toyota Supra MKIII

    Anfang 1986 wurde die dritte Generation des Supra vorgestellt. Sie ist zugleich die erste, die nicht mehr mit dem Namenszusatz Celica vermarktet wurde.

    Celica Supra (MK2)

    Die zweite Generation wurde im Herbst 1981 präsentiert und hatte mit dem neuen (170 PS) starken 6-Zylinder-Motoren einen komplett eigenständigen Antrieb.

    2000GT & Supra MK1

    Der von Frühjahr 1978 bis Sommer 1981 gebaute erste Supra wurde noch als Spitzenversion der Celica zuerst in Japan und später in den USA angeboten.

    BPU Tuning Erklärung | Forum

    Position: Forum » Supra MK4 » Tuning
    Spoony
    Hi
    habe im englischen forum diesen informativen bericht gefunden, original von Homer geschrieben und von der www.mkivsupra.net homepage.
    Finde das ganz interessant, damit sollten keine fragen mehr zum BPU offen sein!!!
    wer langeweile hat kann das ja gerne ins deutsche übersetzen, ist aber super einfach zu verstehen :wink:

    Name:
    BPU

    Also known as:
    Basic Performance Upgrade
    Full decat

    What is it?
    BPU stands for “Basic Performance Upgrade”, a term coined by US firm Suprastore for a basic upgrade package for the TT Supra. BPU is essentially what other marques refer to as "Stage 1” engine modification.

    The BPU upgrades allow the engine to produce more power by raising the boost pressure the turbos produce.

    In stock form, the TT produces 0.76bar (11psi), however this can be raised its is generraly acceptd that the stock ceramic Jspec turbos will handle 1.2bar (17.4psi). The Export spec (UK/Euro/US) has steel blades so will, in general, survive at higher boost pressures. 1.4bar (20.3psi) is not unheard of.

    1.2bar is the "accepted" safe limit with regards to a) detonation, b) actually getting more power, and c) some level of longevity. It is also accepted that you are spinning the cylinder and pulling the trigger each time you use them, but 1.2bar you have one loaded chamber, 1.4bar you've got three
    There are limitations with pressures above 1.2bar, the turbos are already outside of their efficiency range and the additional heat generated will raise the intake air temperature considerably – thus negating the effect of increased boost pressure.

    In both Jspec and export spec, BPU will raise engine power to around 400bhp. Not only will it release more power but it allows much quicker turbo spool-up, which vastly increases drivability.

    How it works
    In stock form, the boost pressure the turbos produce is controlled by back pressure in the exhaust system (I.e. highly restrictive catalytic converters and exhaust system). There are two approaches to BPU dependant on the model of car; as such the next section is split between Jspec and Export spec:


    Fundamentals of BPU

    Jspec:
    To raise boost beyond the stock level the restrictive catalytic converters are removed, thus allowing the turbos to spin faster and produce more boost pressure.

    There is a down side to this. With both cats removed the turbos will in fact over speed far past their safe limit and reach over 1.6bar (23.2psi). This is due to the small size of the jspec wastegate which cannot cope with the increase in exhaust gasses.
    At these pressures the ceramic blades in the turbo can become detached from the shaft and therefore cause catastrophic failure of the turbo.

    In order to add some restriction back in to the exhaust a restrictor ring is added to the exhaust system. A restrictor ring is simply a metal plate that fits normally between either between the 1st and 2nd decat pipes, or the 2nd decat and cat-back. The centre of the restrictor is drilled out to a smaller diameter than the exhaust itself (normally around 2inches). A properly sized restrictor should bring the maximum boost pressure down to 1.2 bar or less.

    UK/Euro/US (Export) spec:
    To raise boost beyond the stock level the restrictive catalytic converters are removed, thus allowing the turbos to spin faster and produce more boost pressure. Different to the jspec, the export spec has a larger wastegate which can handle the increase in exhaust gasses.
    Therefore boost pressure will be maintained at only slightly above stock levels, typically 0.85bar (12.3psi). In order to raise this further it is necessary to install a Boost controller to change the way in which the wastegate opens.
    A restrictor ring is not required on the export spec

    Note: On both models it’s possible to raise the boost with simply adding a Boost controller or Bleed valve; however this is not recommended since the huge resistance of the cats is still in place. This will result in significant extra heat being generated in the manifold and could cause serious engine damage due to raised exhaust gas temperatures.
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