1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Compression Question

Discussion in 'Engine Building' started by 22crazy, Dec 25, 2002.

  1. 22crazy

    22crazy Senior Member

    Messages:
    307
    Likes Received:
    0
    Joined:
    Nov 13, 2002
    what up. Ive been searching the net and asking people but nobody has been able to answer my question. I wouldnt mind building a crazy NA motor but the problem i face is compression vs octane. I no if someone wants to build a NA motor u need high compression, but the problem is that the higher compression u go, the higher octane u need to go. My problem is that in my area the highest octane u can buy at a pump is 94...i can buy octane boosters, but i dont want to buy a booster everytime i go to the pump. Does anyone no whats the highest compression u can have inside your engine using 94 octane before the gas spontaneously explodes because of compression :eek: instead of spark. Thanx
     
  2. xj0hnx

    xj0hnx I wanna be sedated VIP

    Messages:
    14,172
    Likes Received:
    48
    Joined:
    Nov 10, 2002
    Location:
    C.C.TX.
    Articles in above tabs,page 1,detonation ;)
     
  3. 22crazy

    22crazy Senior Member

    Messages:
    307
    Likes Received:
    0
    Joined:
    Nov 13, 2002
    what do u mean page 1....detonation?
     
  4. xj0hnx

    xj0hnx I wanna be sedated VIP

    Messages:
    14,172
    Likes Received:
    48
    Joined:
    Nov 10, 2002
    Location:
    C.C.TX.
    I mean there is a article about detonation that will give you a good idea about the compession question you have in regards to octane levels.
     
  5. 22crazy

    22crazy Senior Member

    Messages:
    307
    Likes Received:
    0
    Joined:
    Nov 13, 2002
    where is the article? if it is the one in articles - detonation it only talks about psi...i need to no the compression of the pistons i need to buy so that it will work with the gas i can supply ( 94 octane )
     
  6. B16

    B16 Super Moderator VIP

    Messages:
    11,539
    Likes Received:
    534
    Joined:
    Sep 30, 2002
    Location:
    yay area, CA
    i think calesta is running 12.5:1 on 93 octane, that is probably the highest i'd go on pump gas
     
  7. 22crazy

    22crazy Senior Member

    Messages:
    307
    Likes Received:
    0
    Joined:
    Nov 13, 2002
    ya 12.5:1 is pretty high too...and i no i can get 94 so i dunno i try messaging him and asking him...thanx for the post b16
     
  8. xj0hnx

    xj0hnx I wanna be sedated VIP

    Messages:
    14,172
    Likes Received:
    48
    Joined:
    Nov 10, 2002
    Location:
    C.C.TX.
    Sorry never said it would give you the exact figures your looking for,just a good idea of the theory and from there the world is yours.
     
  9. 22crazy

    22crazy Senior Member

    Messages:
    307
    Likes Received:
    0
    Joined:
    Nov 13, 2002
  10. phunky.buddha

    phunky.buddha Admin with a big stick Admin VIP

    Messages:
    28,465
    Likes Received:
    228
    Joined:
    Sep 30, 2002
    Location:
    Dallas / Fort Worth, TX

    12.6:1 on 93 :lol:
     
  11. djextremity

    djextremity Senior Member

    Messages:
    963
    Likes Received:
    0
    Joined:
    Sep 29, 2002
    Location:
    in your rearview mirror..wait..
    Don't forget, if you're ever out of your comfort zone where 94 octane is NOT available, you will have to be able to run the highest octane rating available with a bottle of octane booster (usually .6-.8 octane) and not get detonation..just something to think about.
     
  12. davidbr

    davidbr Member

    Messages:
    46
    Likes Received:
    0
    Joined:
    Dec 4, 2002
    would 13:1 safe on 99octane? sorry, but i dont want to make a new thread...
    i know no one can say for real, just guesses
     
  13. IMPORT PRO

    IMPORT PRO Junior Member

    Messages:
    5
    Likes Received:
    0
    Joined:
    Dec 28, 2002
    David

    13.0:1 on 100 octane should work, but might nock and ping from predetination but won't harm the motor.

    for the 94 octane question yes, 11.0:1 will work even for highway use.

    That's coming from a honda/gm technician.
     
  14. pissedoffsol

    pissedoffsol RETIRED

    Messages:
    49,693
    Likes Received:
    54
    Joined:
    Sep 28, 2002
    Location:
    Retirement Home
    and you could always retard the dist. if you had to to get by on a tank of weaker gas, and NOT BEAT ON IT or take it up so high...
     
Verification:
Draft saved Draft deleted

Share This Page