is there anyone out there useing octain booster in there machines, i was just wondering if useing it would hert the moter or not. i have a freind with a 650 griz and he uses av gas mix 60/40 60g/40av and he say it makes a big differance but im not sure if you use it to much what would happen. i tryed some 92octain with a little octain booster and i notest a big differance with the power but im not sure if it good for it any help on this topic would be nice.

 

Hi Octane gas provides no more power than regular gas. The differance is in the fuels ability to control pre ignition knock. If you look up the energy available in the 92 octane versus the 87 you will find it is the same. Some claim that the higher octane is actually a little less potent than the lower octane as the flame front is a little less explosive. There is good information on the net, but you will need to do some research. The only reason fortheoctane boost as well as the higher octane fuels isfor high compression engines that will tend to ignite the fuel early BTDC as the fuel gets very hot as it is compressed and it will light from the heat in the cylynder and not the spark causing the pre ignition knock. Some light knock is normal and acceptable but heavy knock under full load will eventually burn holes in the top of the piston. In my Mazda as an example the engine can be run in winter on 87, but when the weather gets warmer the engine will start to suffer from pre ignition knock. In the summer I am forced to run 92 to reduce the knock. The only advantage other than reducing knock is that a lot of petrol companies add cleaners to the higher octane fuels for keeping the fuel injectors clean.

Cheers Jim

 

Unless your buddy with the Grizzly is running a 13:1 or higher piston, running an av gas blend is a big waste of money,as stated before, octane keep the flame front more stable, and in a stock motor, it may actually not completely burn up, and leave deposites in the combustion chamber. A stock motor will run fine on 87 octane, 89 in hot weather, you should only need 92 if you run 11:1 or higher. Just keep putting regular gas in your quad, and let your friend keep wasting his money.

 

thanks for the replys i tryed some octane booster in my last tank and it felt better but im gonna try the next tank with 87 and see if there is a differance. ya my freind is a die hard racer and thinks av gas is the anser to everything. thanks again.

 

well i just ran a tank of reg through my cat and it seamed slower, maybe its just my imagenation but im gonna try a couple more tanks of reg 87 octane and then try another tank of 94 octane and see if theres a differance. i'll post my results in a few days.

 

Don't let your buddie's so called experience fool you into using av gas. Av gas is formulated for one thing. AIRPLANES!!!! How many people ride at the same elevation as the planes fly??? Not too many that I know of. Planes run at a consistant RPM for long periods of time. There is a person on this forum that is a pilot and could explain in more detail why av gas is not the answer. Send WhoDatInDaMud a pm. He's a very intelligent person, and would more than likely have the answer for ya.

 

Octane levels higher than 90 provide absolutely no performance increase for low compression engines. Listen to the other members' posts. I put avgas in my rancher once, didnt do a damn thing. Top speed didnt change 1mph. High octane is a waste of money, and can cause deposits to build up. Av gas could severely damage your engine when used for a prolonged period of time. Av gas will not boost hp either. It is all in your head, sorry.

 

I may be an aircraft mechanic but I'm not going to profess to be an expert on AV gas. But I'll tell you some of what I know. First of all, It's leaded. that may not be a big deal on the two strokes, but I'm not going to put it into my new 400 Rotax. (As a side note, some small airplanes use Rotax engines, two and four stroke and they say to use regular gas, not avgas.) Avgas is blended for engines that were first built after WWII and haven't changed greatly since. (Even "New" aircraft engines aren't so new) It has additives to help eliminate Carb ice and to prevent high altitude problems (Detonation, ect). As someone already stated, Avgas is made for Airplanes, not quads. And to be fair when asked, mo-gas or Car gas doesn't belong in Airplane engines. But that's another story.

Besides, Avgas is more expensive, and at todays prices, who needs it.

But that's just my opinion.

 

i dident thinkav gas would make a differance in power, but i did want to know if it would hert the moter and it will. but i will say i think 92 or 94 octane does make it run a little better i tryed a tank with 94 octane and 2 tanks without 94 and than another one with 94 and i think it runs better with the higher octane. it might not be a spectaculer improuvement but there is an improuvement at least thats what it feels like to me. also i notist it felt a bit snappier in the bottom end but thats just my opinion.

 

I for one, would love for someone to tell me how avgas will hurt a 4-stroke engine. I mean, I'm hearing people say it's not good for the engine, but nobody says what damage it will cause.

For example, running an engine lean will wear the rings faster, could seize the piston, or melt a hole in the piston. I want to know exactly what damage will be done by running avgas.

Waylan