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Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 12:19 pm
by RCPlayland
I usually get premium 91 octane. Every once in a while I find 92 octane. It runs good for the set up I have.

(V&H full exhaust, V&H power pack set to 1 setting below drag racing, and stage 3 jet kit)

I found out yesterday that there is a local gas station that has 100 and 110 octane. The 110 is illegal for street use, so I opted for the 100.

At $7.95 a gallon.... $23 to fill. I was immediately impressed after getting 10 blocks away.

My settings on my power pack usually loads up at the lower rpms (2-4k) when tooling around town and bogs for a second when nailing the throttle.

After putting 100 octane in.... wow... no dead spots, excellent throttle response, and wow oh wow it feels the bike wants to launch from out under me.



I don't think I will use this that often due to the price... ouchy! But a once a month fill up probably will be in the works.

Anyone else try this?

Oh, also the exhaust fumes smell totally different! Almost smells like rubbing alcohol, or something like that.

So far I have only used 1/2 of the tank and can't wait till tonight to burn off the other 70 miles!

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 12:24 pm
by YAM93
It would be nice if any gas station in our area had something like that, but alas, they don't.

I usually use 93, works great.

Most of the guys who are placing top 10 in local motocross races are using VP race gas, which I believe is 100 or 110 plus oxygenation. I've never tried it, the YZ250F doesn't need any more power at my skill level, well, at least YET. haha! maybe next year.
:banana: :headbang:

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 12:28 pm
by cad600
I've thought about it. But the closes gas station that has 100 octane is a 50 mile round trip. So not very usefull to me. I even thought about buying it by the barrel. But I can't justify paying $300-$500 at a crack for gas, at least right now.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 12:29 pm
by ragedigital
I run only 87 octane unleaded. Unless you're pre-dentonating, stick with the lower octane. Your fuel will burn quicker.

That 100+ stuff is usually "leaded".

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 1:13 pm
by Fartblood
I don't think the higher octane will be responsible, as the Fizzer doesn't have the ability to advance it's ignition to take advantage, and unless you've done some headwork to up the compression there'll be no gain there either.

More likely is that it's a more expensive fuel and has detergents (to clean the combustion chamber) and other chemicals to enhance or even the burn.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 2:09 pm
by manveru
i run 85 octane with no problems, the highest available anywhere publicly(not at a track) is 91.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 2:45 pm
by ThisEndUp
Fartblood wrote:I don't think the higher octane will be responsible, as the Fizzer doesn't have the ability to advance it's ignition to take advantage, and unless you've done some headwork to up the compression there'll be no gain there either.

Agreed




Fluff

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 3:07 pm
by cad600
manveru wrote:i run 85 octane with no problems, the highest available anywhere publicly(not at a track) is 91.
Where do yo live? California? In Atlanta premium gas is 92 octane, sometimes 93. There use to be a couple of stations that sold 100 octane but there gone now. I know in California they only get 91 octane which I've heard refered to as "california piss water" because they can't get 92 or higher.

You can still buy 100-104 octane unleaded fuels that are street legal, but most of them require you to buy per some sort of barrel size.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 3:11 pm
by sweekster
cad600 wrote:
manveru wrote:i run 85 octane with no problems, the highest available anywhere publicly(not at a track) is 91.
Where do yo live? California? In Atlanta premium gas is 92 octane, sometimes 93. There use to be a couple of stations that sold 100 octane but there gone now. I know in California they only get 91 octane which I've heard refered to as "california piss water" because they can't get 92 or higher.

There was a time when we could get 93 but. Long gone are those days :mad(

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 3:19 pm
by ragedigital
cad600 wrote:You can still buy 100-104 octane unleaded fuels that are street legal, but most of them require you to buy per some sort of barrel size.
http://www.vpracingfuels.com/index2.html

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 3:27 pm
by Luke-a-Tron
The reason you're getting more power is because these fuels burn hotter/faster. As Fartblood (I shudder every time I type that name) mentioned, the higher octane rating has little to do with it since the bike is not set up to take advantage of it. You do need to be careful with that as you can burn your valves or even your pistons. The stuff is not meant for stock motors.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 4:29 pm
by megaloxana
I'm surprised you had such a good result from that...no placebo?

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 5:13 pm
by Luke-a-Tron
No, there's actually a performance gain to be had from the fact that those fuels contain a higher energy density per volume. They are cut with things that are not gasoline specifically to make the flame front move faster. This gets to be important when you have a large piston and high revs. If the fuel doesn't burn fast enough, combustion will not be able to keep up with the rate at which the piston is moving away. At that point the fuel is physically limiting the engine from producing more power.

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 5:18 pm
by RCPlayland
It's cool...

I think the most noticeable thing is that my settings with the V&H system I have puts the most power at high rpms. So even after I get it dyno'ed later on I probably will still load up at lower rpms.

With the 100 octane it pretty much eliminated that.

Anyhow. I just got excited to feel the extra umph and instant throttle response.

Whoot!

Re: Differences in Octane! I tried this and WOW!

Posted: Mon Aug 18, 2008 5:22 pm
by manveru
cad600 wrote:
manveru wrote:i run 85 octane with no problems, the highest available anywhere publicly(not at a track) is 91.
Where do yo live? California? In Atlanta premium gas is 92 octane, sometimes 93. There use to be a couple of stations that sold 100 octane but there gone now. I know in California they only get 91 octane which I've heard refered to as "california piss water" because they can't get 92 or higher.

You can still buy 100-104 octane unleaded fuels that are street legal, but most of them require you to buy per some sort of barrel size.
I live in colorado.

Higher octane fuel actually burns slower to prevent detonation. As compression and timing increase so does the combustion chamber temperatures. with lower octane fuel it will ignite sooner and detonate.