I know that some Sunaco stations ell the 110 Race fuel

 

A, no. Pre-ignition is lighting the mixture too soon caused by the heat of compression. It lights the mixture off before the plug can light it off. The fuel gets too hot and lights to soon. Higher octane fuel .perventsthis. Higher cetane makes this "bad" thing happen. The octane value has nothing to do with the heat value of the fuel. Although most race fuels have a higher heat value than pump gas'es. That is why people have said I feel more power when I run race gas, even on a stock engine. That is possible because it has more energy/ lbs.

Running high octane race gas in a stock engine will do several things for you. Make you spend lots of money. Clean up a Sooty engine. Smell really good too the guy in back of you. In "some" cases, make more power. (some cases loose power) But you can tune it to make more power.

All in all, use the proper octane your engine calls for. Unless you have a few buck in your pocket and want to smell cool!!!

 

sunoco, vp, klotz, etc sell 110

 

I use 89. It's not a high comp motor so it doesn't need anymore.

 

The higher octane burns slower. So unless you have your timing advanced enough, you can possible fire the spark BEFORE the piston reaches TDC. Maybe I am just thinking on automotive terms.

 

You want to light the mixture before TDC. The whole game is to match the highest pressure to match as the exact same time the piston gets to TDC. For example: If you are using a high octane fuel, like you said it burns slow, so you want to start the spark sooner in the combustion cycle to get the burn started earlier. If you have a “fast burn fuel” you can let the piston get closer to TDC before you light the mix because it burns fast. Make sense?

Some fuels have very high BTU’s (energy) but very low octane. Diesel is one. Things get even more confusing. Some fuels have very low BTU’s, low octane and also a slow burn rate. Nitro methane is one.

For very slow fuels, like nitro methane, you have to have big time advance BTDC. 50 to 60 degrees of timing advance is common. Even with this much lead you still have raw fuel burning out the pipes. That gives you an idea of how **** poor of a fuel, and how slow nitro burns.

The bottom line is: Match your octane rating to your engine and conditions. Just make sure you have more octane than you need, otherwise ugly things will happen inside of your engine. If you use more octane then you need, you will just spend a few more bucks more on fuel, but nothing bad will happen to your engine. If you have a stock engine just read the manufactures recommendations. If you have a "non-stock" engine then you will have to ask the engine builders recommendations.

 

i want 104 octane for a 14.1 high compression head and i want to use 94 octane and mix it with octane boost to get 104 dose the stuff really work or not

 

I agree with DoctorTurbo about using AT LEAST the minimum recommended octane, higher won't do any harm, within reason. Any gas you can commonly buy at the pumps won't have a high enough octane rating to do any damage, IMO. My Honda calls for 87 octane regular unleaded, to the best of my knowledge. However, whenever I can, I use the premium 91 octane unleaded. Why? An engine that runs hot, and under fairly high load and low rpm, such as an aircooled quad engine, is prone to detonation. By using a higher octane fuel, you reduce the possibility and duration of detonation, which is a Very Good Thing [img]i/expressions/face-icon-small-happy.gif[/img]. As near as I can tell, it costs me about 75 cents a tankful more to run high test.

 

xxxracerxxx if you are asking me can you get 104 octane with pump gas and an octane additive, I would have to say I don't know of a product that will do that. Products like"104" (trade name) will only increase your octane 2 to 5 points. Take your 94 base stock and add this product to it and you will come up very short of your 104 number. Are there products on the market that will add 10 points of octane? I just don't know. When I did these kinds of mods I would only burn race gas.

14 to 1 is big time. Your in the big leagues now. If I were you, I would only burn race fuel. If you knew how to read plugs real well then you could buy a fiver of race fuel and then cut it lets say 25% and check your plug. Go down until you see some signs and then jack it up 10% and you will be safe and save some money at the same time.

 

Just found the Octane recommendation in my '04.5 SPortsman Manual. It says use a gasoline with a MINIMUM rating of 87 leaded OR unleaded. It doesn't specify any limits on the high end but that is probably an assumption that most people don't have anything more than 91 available to them.

I'm going to try a tank full of aviation fuel that I squirt in the airplane. It's 100LL (low lead) and clean burning stuff. It'll be interesting to see the difference...if any.