Octane to compression ratios?

[dubs LT]

I reciently traded a buddy an extra swing arm for his cool head with 19 and 22 domes. My Quad measured 195 psi when I rebuilt it and I run BP92, so the 22 dome no worries. But the 19 dome Im sure im going to need to run a high oct rating fuel.

Is there a chart or how do I figure out what my optimum oct rating should be based on my comp ratio and Alt?

Any ideas what i should see for compression numbers with that 19cc dome?


Thanks

aaron

[2000BansheeBoy]

I've been told a thousand times by a hundred different people that since I'm running a 19 that I'd be OK to run 92, but race fuel will make sure that it doesnt blow up my shee. I'm gonna try av. gas soon, then maybe a 50/50 of VP110 and 92

[Bad Intentions]

your prolly lookin at being around 200- 205 psi with the 19cc dome if i had to guess. id check to make sure,my banshee was at 212 with my 17cc domes, id run 110 octane even with 195, thats where my shee is at right now and i run 110

[Mert]

Originally Posted by Bad Intentions

your prolly lookin at being around 200- 205 psi with the 19cc dome if i had to guess. id check to make sure,my banshee was at 212 with my 17cc domes, id run 110 octane even with 195, thats where my shee is at right now and i run 110

i was about to say, I heard that anything over 190 needs higher octane than pump fuel, what octane is av fuel and about how expensive is it?

[Bad Intentions]

Originally Posted by Mert

i was about to say, I heard that anything over 190 needs higher octane than pump fuel, what octane is av fuel and about how expensive is it?

i believe the more common places to get av gas like sunoco is 101 octane,not positive but if i remember correctly it is between 101 and 103. not sure of price because i never considered using it.i used premium up untiul i did all the work to my motor and bumped up the compression then went to 110. i dont know why people do the whole 50/50 mix its such a waste of time when 110 is so easily available. you might save at most 3 or 4 bucks by mixing,if you ask me just get some good quality 110 if you need a higher octane fuel and call it a day.someone here said they were gonna do a 50/50 mix of 110 and 92? with an overall 5 gallon mix your only up to 95 octane. why waste your time and effort to get your octane up by 3? what the hell is the difference between 92 and 95 ya know.just spring for the better fuel,being the 110, the bike is going to run much better with the 110 than 95 or even the av gas for that matter.av gas is garbage,for one most aviation fuels are leaded, and nobody realizes the fuels are made for high altitude use(hence av gas) the molecular make up was made to burn at higher altitudes and higher manifold preasures.also depending how rich or how lean the motor is running the octane will vary by a few numbers. just read up on av gas and you'll see 110 race fuel is the best way to go for a higher compression motor.

[strokeittwice443]

i agree with above statement, you will be fine with pump gas with the 19cc domes. i run CAM-2 race fuel all the time in my shee and only have 20cc domes, just a personal preference.