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jols
03-18-2009, 08:59 PM
The premium fuel i use here is 91 octane with no ethenol. I'de like to bump this up a bit using the LUCAS octane booster i bought. How much should I use and is running too much octane in this CFI dangerous?? Is anybody else doing this as well??

nmmiles
03-18-2009, 09:01 PM
don't do it. They don't effect your octane hardly at all. Use the search function, a few months back I remember a thread about it, it came out to adding decimal amound of octane to the overall level in the fuel.
Just my .o2

Nolan

guidoxpress
03-18-2009, 10:13 PM
nolan is right..

octane boost is a joke..spend the $5/8 bottle of octane boost on some AVGAS or race fuel..

if you ran 20% in a tank you will be setup good..

or find 94 octane in your town..

nmmiles
03-18-2009, 10:19 PM
sean,

what is the difference between avgas and 110 race gas? I never really read anything that shows the answer?
I see the thread below about av gas. But what is the stuff? I've never head of it other than SW. I just assumed that AV gas was short, or a form of 110 race gas.
Thanks,
Nolan

Sorry about jumping thread, just a quick question ;)

skibreeze
03-18-2009, 10:25 PM
If you have a stock motor, 91 is just fine.

theultrarider
03-18-2009, 10:28 PM
If you are running a stock motor you are just throwing your money away throwing more octane at it than the 91 it calls for. You can actually cut down the performance with too much octane. And btw, here in Alaska the best pump gas we can get is only 90 octane. Nobody is mixing any race gas or boosters in their Polaris's and not having issues soley on the fuel.

guidoxpress
03-18-2009, 10:32 PM
sean,

what is the difference between avgas and 110 race gas? I never really read anything that shows the answer?

Thanks,
Nolan

Sorry about jumping thread, just a quick question ;)

no sweat..

AV GAS is usually around 100 octance..

Race Fuel can be different between brands..Sunoco Fuel is 112 octane, Renegade is like 110 octane..

like the others said above..if your running a stock motor then 91 is fine..if your running NOS then you NEED to bump your octance for sure..to prevent detonation...

for example..i have a 10.8/gal fuel tank on my 900...if i ran 8gallons of 91 octane..with 20% (2 gallons) 110 race fuel, i will have about 94 octane combined and that is good to use with NOS..AV GAS will need more like 50/50 AVGAS and 91 octane..

make sense..:D

happylilcuss
03-18-2009, 10:51 PM
Also AV gas is just short for aviation fuel. You can find it at your local airport.

BB454
03-19-2009, 08:44 AM
Octane is one of those love hate things. High octane burns colder and is used to prevent detination. It actually makes less power. Low octane burns hotter and heat is power but can cause pre ignition or detination. So it's a love hate relationship. Low octane and make heat and power but you may detonate or high octane and no detination but not as much power.

Use the lowest octane that you can without detenation for the best power.

bashawrob
03-19-2009, 09:25 AM
no sweat..

AV GAS is usually around 100 octance..

Race Fuel can be different between brands..Sunoco Fuel is 112 octane, Renegade is like 110 octane..

like the others said above..if your running a stock motor then 91 is fine..if your running NOS then you NEED to bump your octance for sure..to prevent detonation...

for example..i have a 10.8/gal fuel tank on my 900...if i ran 8gallons of 91 octane..with 20% (2 gallons) 110 race fuel, i will have about 94 octane combined and that is good to use with NOS..AV GAS will need more like 50/50 AVGAS and 91 octane..

make sense..:D

One other thing worth mentioning; av gas is extremely dry. They add a lot less additives particularely top end lubricants. I cringe every time I hear a hot rodder tell me he uses av gas in a vehicle. In a sled, I don't know what the effect would be. Less lubricant, but you're adding it back in with the oil. If I had to run av gas in my sled I would probably toss a bit of oil in with it.
There's my .02

storeytellin
03-19-2009, 10:06 AM
Great thread all, really good information. Thanks