octane

[banshee_terror_]

i have a mild dune port with the timing at +4 at 450ft elevation and i have 21cc domes and the compression im guessing is around 90 to 110. am i going to b safe to run 91/93 octane..... i think i spelt that wrong

Edited June 5, 2009 by banshee_terror_

[Bill]

If your compression is only 90 to 110 id say its time for a rebuild, are you sure you checked it right?

[banshee_terror_]

If your compression is only 90 to 110 id say its time for a rebuild, are you sure you checked it right?

 

 

yah its fine

[TwistedSheeRida]

if there is more than a 10 psi spread you should rebuild to. no it is not fine you have domes. and it is 90 110? im at like 150 stock head

Shit run some diesel through it should be fine with that compression lol

[banshee_terror_]

no im guessing my compression is around 90 to 110. like i just rebuilt the motor and never comp tested it. and with port jobs you loose compresion. so with like 21cc domes i figured id make around 90 to 110.

[dirtydownunder]

compression should be within 10% of each other if its not, time for rebuild.

guessing compression is .. i cant even think of something funny to say but yeh dont guess.

 

 

 

fyi diesel needs freekn heaps of compression to combust.

[278]

If your motor is built right theres no way its 90-110 if I were to guess I'd say 155, and guessing is not a good thing to do. Get it checked

[Loc]

Stock bike should be around 120psi at that elevation. I would do a compression test before making any guesses. As far as the fuel anything under 150psi is safe for octane rating of 91 and above.