• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

High comprises vs lower octane.

F

fitler

Active member
May 14, 2009
201
33
28
right off the bat forgive me if I use any of the wrong terminology in this.

My question is if you raise the compression by swaping the head to a higher compression head requires you to mix run race gas to slow the ignition or combustion? ( I know not all heads require race gas).

Would running a lower octane that burns faster like ethonol 87 have the same effect as raising the compression and then running race gas?

I know you can only really get away with lower octane at higher altitudes but ride at 8000 and up.

Does anyone understand what I'm getting at? Higher compression and higher octane vs stock compression and lower octane. While riding at high altitude.
 
I

inspector01

Well-known member
Mar 21, 2013
379
297
63
MN
right off the bat forgive me if I use any of the wrong terminology in this.

My question is if you raise the compression by swaping the head to a higher compression head requires you to mix run race gas to slow the ignition or combustion? ( I know not all heads require race gas).

Would running a lower octane that burns faster like ethonol 87 have the same effect as raising the compression and then running race gas?

I know you can only really get away with lower octane at higher altitudes but ride at 8000 and up.

Does anyone understand what I'm getting at? Higher compression and higher octane vs stock compression and lower octane. While riding at high altitude.

No, the power increase comes from the increased compression not the fuel or the octane to compression ratio. The fuel is only there to allow that high compression to work. However, you can lose power by running too high of octane as well, so yes sometimes lower octane makes more power than higher octane fuel, but still less than an equivalent engine with higher compression and adequate fuel.
 

blastco2

Well-known member
Lifetime Membership
Dec 27, 2012
315
106
43
se idaho
The wiki article titled "octane rating", does a good job of explaining the whole octane, compression, hp thing. :light:
 
Premium Features