Beberapa parameter yg mempengaruhi kebutuhan oktan gasoline
Scuto Laminating Simota Gelap.net

25 Mei 2016 - Payment System Terbaru Untuk Bursa Jual Beli telah kami hadirkan.
Untuk informasi lebih lengkap dapat dilihat di http://modifika.si/630917

Page 1 of 3 123 LastLast
Results 1 to 10 of 27
  • Thread Tools
  • Short URL:  http://modifika.si/15694
  • Share on facebook
  • Share on twitter
  1. #1
    Letnan Jendral
    Location
    Banten
    Posts
    25,662
    Power
    100 
    M-Store Point
    0
    Online
    1 Mth 3 Wks 2 Days 46 Mins 9 Secs

    Beberapa parameter yg mempengaruhi kebutuhan oktan gasoline

    Beberapa parameter yg mempengaruhi kebutuhan oktan gasoline sebuah kendaraan bermotor

    Selain parameter compression ratio. ;

    jadi supaya mobil peminum pertamax kita bisa minum premium dan
    disubsidi negara namun mengorbankan engine output dan konsumsi bbm
    kendaraan perlu dilakukan langkah* berikut:

    1. pakai thermostat dengan suhu bukaan yg serendah rendahnya
    2. pasang mekanisme cold air intake
    3. usahakan udara yg dihisap engine lembab (water injection misalnya)

    tambahan

    ber-karbu: set lambda (afr) dibawah satu dan mundurkan timing pengapian.

    ber-turbo: copot turbo, ber-efi: remap ecu (?)

    http://www.serayamotor.com/diskusi/viewtopic.php?p=122056#122056

    Sebenarnya persyaratan octane gak hanya bergantung dari Compression Ratio saja
    tapi ada beberapa parameter lainnya seperti :

    1. Ukuran Diameter Silinder ... Semakin besar ukuran Diameter Silinder, maka
    akan memerlukan Oktane yang lebih besar/tinggi. Seperti halnya ukuran diameter
    silinder untuk pesawat terbang yang menggunakan mesin piston ... diameternya
    besar (diperlukan untuk cruising) ... maka akan memerluka oktan yang besar ...
    umumnya untuk pesawat nilai Oktan-nya adalah RON100.

    2. Kepala Silinder (Cylinder Head) yang menggunakan bahan BESI COR akan
    memerlukan Oktan yang lebih tinggi ketimbang menggunakan Bahan ALUMINIUM.

    3. Campuran Udara BBM (AFR) yang LEAN/KURUS akan memerlukan Nilai Oktan yang
    lebih besar.

    4. Engine Coolant Temperature ECT, semakin tinggi temperaturenya maka akan
    memerlukan Oktan yang lebih tinggi. Umumnya yang paling IDEAL adalah 73 oC ...
    namun kebanyakan mobil menggunakan Thermostat dengan rating temperature di atas
    80 oC.

    5. Timing Pengapian yang dimajukan (Advanced Timing), juga akan memerlukan
    Oktane yang lebih tinggi. Jika menggunakan Bensin dengan Oktan yang
    lebih rendah
    ... maka ECU akan mengundurkan Timing Pengapian.

    6. Intake Air Temperature (Suhu Udara Masuk), semakin tinggi maka memerlukan
    oktan yang lebih tinggi.

    7. Kelembaban (Humidity) ..... Udara yang Kering (kelembabannya rendah) akan
    memerlukan nilai oktane yang lebih tinggi.

    8. Tekanan Barometer Udara, ... semakin tinggi tekanan barometer Udara ...
    diperlukan oktan yang lebih tinggi.

    9. Ketinggian Tempat ... Jika tempatnya adalah dekat dengan laut (sea Level)
    maka akan memerlukan oktan yang lebih tinggi. Semakin tinggi tempatnya maka
    semakin kuranglah persyaratan nilai oktannya.

    --
    Terima Kasih.

  2. SbcAgent
  3. #2
    Sersan Mayor
    Location
    Jakarta
    Posts
    965
    Power
    M-Store Point
    0
    Online
    N/A
    bener inih?

  4. #3
    Kapten
    Location
    Bogor-Jakar
    Posts
    2,160
    Power
    M-Store Point
    0
    Online
    1 Wk 3 Days 12 Hrs 43 Mins 21 Secs
    mo tanya ttg no.3 :

    maksudnya gimana ya?
    kebanyakan udara n kurang fuel , maka oktan harus tinggi
    atau
    kurang udara n kebanyakan fuel yg memerlukan oktan tinggi ?

  5. #4
    Mayor Jendral
    Location
    In your dreams...
    Posts
    15,312
    Power
    23 
    M-Store Point
    0
    Online
    4 Hrs 28 Mins 49 Secs
    wawwww

  6. #5
    Kapten
    Location
    eNZed
    Posts
    2,003
    Power
    M-Store Point
    0
    Online
    8 Hrs 56 Mins 27 Secs
    Quote Originally Posted by [Ctrl
    +[Alt]+[Del]]mo tanya ttg no.3 :

    maksudnya gimana ya?
    kebanyakan udara n kurang fuel , maka oktan harus tinggi
    atau
    kurang udara n kebanyakan fuel yg memerlukan oktan tinggi ?
    maksudnya, kalo AFR (air/fuel ratio) elo lean (irit ato diatas 1:14.7), lo perlu bhn bkr yg beroktan tinggi yg notabene lbh gampang terbakar. krn dgn afr yg lean, bhn bkr sgt sulit utk terbakar krn 1 & laen hal.

    ada yg bs jelasin? gw bingung jg nih..

  7. #6
    Sersan Dua
    Posts
    241
    Power
    M-Store Point
    0
    Online
    N/A
    Mmmm... ini sih ngambil fakta sepotong2 terus narik kesimpulan yang salah.

    Let's start with octane number.. What is it?
    It's the number that tell you about the quality of fuel that you put in your gas tank.
    The reason you have to pay Rp 6600,- for every liter of PertamaxPlus (PP) instead of Rp 4500,- for a subsidized Premium is because PP is more resistant to detonation compared to Premium. And again, your motor doesn't like detonation.

    So now, what is detonation..?
    In the internal combustion motor, like my beloved K20, the combustion process can be happened by two means. The proper way is being lit by spark plugs, or what we call ignition. The other one is the devilish 'detonation', which happened when the 'air/fuel mixture' (a/f) is auto ignited by itself due to high temperature or high pressure inside the cylinders.

    Just a hypothetical example...
    When the well-paid engineers in a Honda factory designed the motor, they already have in mind about the typical user of the motor.
    When they designed a motor for the performance oriented Civic-R, they knew that whoever buy that car won't complain about the high price of 100-octane gas, because the main interest for that kind of market is performance. They already paid so much for the price of the car, so they want to enjoy its performance. So they can designed a motor with 11+:1 compression ratio (CR) for this car.

    But when they designed the motor for a budget oriented sub-compact like Jazz, they have to consider that this segment is very price sensitive, including to its operational costs. So they have to put the CR of L15 motor to a moderate number, which still can tolerate the possibility of some misinformed cheap users putting an 88-octane fuel in its gas tank.

    So, pay attention to CR and fuel requirement of the motor before you buy a car. 'Playing Engineer' with your motor to save some penny will cost you more in the end.

    Once again kids, there is no replacement for octane number to resist detonation.

    I'll be back next week to dissect every point mentioned on the original post above.
    Huhuuhuuuu...

  8. #7
    Sersan Dua
    Posts
    241
    Power
    M-Store Point
    0
    Online
    N/A
    Quote Originally Posted by theansoracing
    1. pakai thermostat dengan suhu bukaan yg serendah rendahnya
    I know that the logic behind this statement is high cylinder temperature is more prone to detonation. And it demands a high octane fuel to resist the detonation.
    It's true if your motor is running too hot. But installing a lower temp thermostat is not the right mod, why?

    Again, the well paid engineers on the Honda factory already calculated the optimum temperature for the motor to run.
    Running too cold will only make the air/fuel mixture (a/f) harder to ignite.
    They already picked the right kind of thermostat where it will circulate the coolant fluid to radiator when the motor temperature exceed that point.

    If running cold is always better, then why they installed the thermostat in the first place. It will be easier, and cheaper, to just circulate the coolant since the motor is started.

  9. #8
    Sersan Dua
    Posts
    241
    Power
    M-Store Point
    0
    Online
    N/A

    Re: Beberapa parameter yg mempengaruhi kebutuhan oktan gasol

    Quote Originally Posted by theansoracing
    2. pasang mekanisme cold air intake
    Again, the logic behind this statement is: colder intake air temp -> colder cylinder temp -> less prone to detonation -> it's ok to use lower octane gas.

    Let me ask you this, how cool is your intake air temp after you install the cold air intake (CAI)? Will it be able to compensate the high temp in the cylinder chambers due to high compression ratio (CR)?

    While I'm not one of those well paid Honda engineers, I could assure you that the CAI only drops your intake air temp a couple of degree, which is next to negligible because as soon as the air enters the combustion chamber, the high CR of your motor will push the temperature so high that it will detonate anyway (if you insist on using the cheaper low octane gas).

  10. #9
    Sersan Dua
    Posts
    241
    Power
    M-Store Point
    0
    Online
    N/A
    Quote Originally Posted by theansoracing
    3. usahakan udara yg dihisap engine lembab (water injection misalnya)
    The logic behind this statement is: extra moisture -> absorb heat in the combustion chamber -> it's ok to use lower octane gas.

    It's true that extra moisture in the air/fuel mixture could absorb some heat in the combustion chamber, and that's the logic behind a rich air/fuel ratio could resist detonation. Actually, it's the method used by engine tuners to resist detonation in high engine load. Introduce more fuel to wicked away heat. But a the same time, if your intention is to save money on gas, running rich will only cost you more since you spray more fuel than what is necessary.


    But what about if I use water injection..? Water is cheaper than gas.

    If the fluid that you inject is water, it will make your air/fuel mixture harder to burn. Which will lead to ineffective power stroke, less power, and in the end more frequent trips to gas station since the driver will tend to floor the throttle all the time.

  11. #10
    Letnan Dua
    Posts
    1,224
    Power
    M-Store Point
    0
    Online
    1 Wk 3 Days 10 Hrs 33 Mins 9 Secs

    Re: Beberapa parameter yg mempengaruhi kebutuhan oktan gasol

    Quote Originally Posted by ikanhiyu
    Quote Originally Posted by theansoracing
    2. pasang mekanisme cold air intake
    Again, the logic behind this statement is: colder intake air temp -> colder cylinder temp -> less prone to detonation -> it's ok to use lower octane gas.

    Let me ask you this, how cool is your intake air temp after you install the cold air intake (CAI)? Will it be able to compensate the high temp in the cylinder chambers due to high compression ratio (CR)?

    While I'm not one of those well paid Honda engineers, I could assure you that the CAI only drops your intake air temp a couple of degree, which is next to negligible because as soon as the air enters the combustion chamber, the high CR of your motor will push the temperature so high that it will detonate anyway (if you insist on using the cheaper low octane gas).
    i think it's not just about the temperature, it's about the density of the air. more dense air that engine suck, more power they produce, right?


    Quote Originally Posted by ikanhiyu
    Quote Originally Posted by theansoracing
    3. usahakan udara yg dihisap engine lembab (water injection misalnya)
    The logic behind this statement is: extra moisture -> absorb heat in the combustion chamber -> it's ok to use lower octane gas.

    It's true that extra moisture in the air/fuel mixture could absorb some heat in the combustion chamber, and that's the logic behind a rich air/fuel ratio could resist detonation. Actually, it's the method used by engine tuners to resist detonation in high engine load. Introduce more fuel to wicked away heat. But a the same time, if your intention is to save money on gas, running rich will only cost you more since you spray more fuel than what is necessary.


    But what about if I use water injection..? Water is cheaper than gas.

    If the fluid that you inject is water, it will make your air/fuel mixture harder to burn. Which will lead to ineffective power stroke, less power, and in the end more frequent trips to gas station since the driver will tend to floor the throttle all the time.
    water injection is not use as fuel, water injection is use because water absorb more heat than air/fuel mixture
    correct me if i'm wrong....

 

 
Page 1 of 3 123 LastLast
Venom 300x250 NGK Busi

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. ada yg punya T/S parameter tweeter ribbon Fountek NeoCD1.0
    By ice_audioworkshop in forum Diskusi Speaker
    Replies: 3
    Last Post: 22nd October 2011, 16:02
  2. Replies: 90
    Last Post: 27th October 2010, 15:16
  3. Setting parameter Sub woofer di 9887
    By christna in forum Diskusi Subwoofer
    Replies: 4
    Last Post: 9th December 2008, 08:20
  4. Parameter Input Piggyback
    By sate777 in forum Diskusi Mesin
    Replies: 2
    Last Post: 12th September 2008, 06:36
  5. Ask>> midbass MP5 6" : parameter T/S atau data LM
    By permet in forum Diskusi Speaker
    Replies: 7
    Last Post: 4th December 2007, 12:09
Back to top