Race Fuel, Help Me Understand

[Hotfoot]

Possibly this topic has already been covered in this forum, but I didn't find it so here goes: What's the deal on race gas? Is it worth anything to use it? I have asked people around the track and gotten such a wide variety of answers that I'm more confused than ever. My bike is stock, and I've been running pump gas unleaded 91 octane. I can buy 100 or even 110 octane unleaded pump gas, but I'm in California so who knows what is added to it. At the track there's a fuel guy that sells mysterious and expensive cans of stuff labeled with numbers and letters. One day he told me I could run leaded race gas and get 2-3 more hp (sorely needed on my bike) but I think he must have thought I had a straight race bike with no emmission control stuff on it; doesn't it do bad things to your catalytic converter to run leaded gas?

 

Someone else told me that since my Power Commander is mapped for 91 octane, I would get no benefit from higher octane fuel unless I remapped it. Others have suggested that it takes even more modification than that to get the benefit. And I've also heard that race gas simply isn't worth the expense. But, judging by the smell coming from a lot of bikes on the track, a lot of people ARE using it, presumably they have a reason... Can anybody clear this up for me?

[hubbard_28]

Hotfoot, I don't know. But EVERYONE who uses race fuel swears by it. If you were to try it, the potential damage to the engine or parts would be so miniscule, and take such repeated use to actually damage your engine. There's only one way to find out..... grab a can of that overpriced stuff and pour it in. I'm going to do it if I can get my hands on it Sunday. If I do, I'll let you know what I found.

[sleepr]

I don't run it in my racebike, but more because I'm cheap and right now I can gain more horsepower, more economically by losing weight myself. I do race with a number of people that use it and know that you have to be careful with it's handling. Anyone here who uses it drains it in the off season because it does not sit well in the rest of the fuel system when it get's down to -40 C!

[stuman]

First off, high octane fuel will do NOTHING for performance. High octane fuel is only meant to resist detonation in high compression motors. So unless you have milled your head or have different pistons you actually want to run the lowest octane fuel you can for your bike. Low octane fuel is more volatile and will produce more power. As long as the engine doesn't ping or knock on a lower octane fuel.

 

 

 

Real race gas is a whole other story. Fuel like VP MR9 or Ultimate 4.2 will produce more power. To get the most out of race fuels like this you should map the bike for it as they tend to make a bike run lean. These fuels produce more power because they are oxygenated, not because of the octane rating.

 

 

My ZX10 makes about 5 more HP on race gas then it does on pump gas, but it was mapped for race gas. If you mapped it for each type of fuel the difference would probably be less, maybe 3hp. On a typical race weekend I run pump gas in practice and race fuel durring the race.

 

The things is on a 600 you MIGHT get 2-3 more hp out of ultimate 4.3 or maybe as much as 5hp out of the more expensive stuff like MR9.

 

Is 2 hp really going to make a difference? Well, if your racing at the front maybe...

[Cobie Fair]

Stu--thanks for some real numbers.

 

I'd read an article some years ago in RW, what I recall was unless you had done work to the engine (like you mention, milling the head, etc.) then you were likely going to lose over pump gas. Not sure if the oxygenated fuels you are referring to were available then (say 2000). Do you know by chance?

 

C

[chopperbill]

First off, high octane fuel will do NOTHING for performance. High octane fuel is only meant to resist detonation in high compression motors. So unless you have milled your head or have different pistons you actually want to run the lowest octane fuel you can for your bike. Low octane fuel is more volatile and will produce more power. As long as the engine doesn't ping or knock on a lower octane fuel.

 

 

 

Real race gas is a whole other story. Fuel like VP MR9 or Ultimate 4.2 will produce more power. To get the most out of race fuels like this you should map the bike for it as they tend to make a bike run lean. These fuels produce more power because they are oxygenated, not because of the octane rating.

 

 

My ZX10 makes about 5 more HP on race gas then it does on pump gas, but it was mapped for race gas. If you mapped it for each type of fuel the difference would probably be less, maybe 3hp. On a typical race weekend I run pump gas in practice and race fuel durring the race.

 

The things is on a 600 you MIGHT get 2-3 more hp out of ultimate 4.3 or maybe as much as 5hp out of the more expensive stuff like MR9.

 

Is 2 hp really going to make a difference? Well, if your racing at the front maybe...

 

 

I'm currently having a Nemesis ECU installed in my Bike,(Ducati 749r). This ECU has the capability to have multiple maps installed that can be switched at the starter button. One map will be for pump gas and another will be for oxygenated race gas. The numbers I have heard are about 5 more HP on race gas. Does that make a difference? Only when I'm on the straights and the guy next to me is on a Susuki 750(750 SB) or a 1098 (open twin) classes........

[Jaybird180]

First off, high octane fuel will do NOTHING for performance. High octane fuel is only meant to resist detonation in high compression motors. So unless you have milled your head or have different pistons you actually want to run the lowest octane fuel you can for your bike. Low octane fuel is more volatile and will produce more power. As long as the engine doesn't ping or knock on a lower octane fuel.

 

 

 

Real race gas is a whole other story. Fuel like VP MR9 or Ultimate 4.2 will produce more power. To get the most out of race fuels like this you should map the bike for it as they tend to make a bike run lean. These fuels produce more power because they are oxygenated, not because of the octane rating.

 

 

My ZX10 makes about 5 more HP on race gas then it does on pump gas, but it was mapped for race gas. If you mapped it for each type of fuel the difference would probably be less, maybe 3hp. On a typical race weekend I run pump gas in practice and race fuel durring the race.

 

The things is on a 600 you MIGHT get 2-3 more hp out of ultimate 4.3 or maybe as much as 5hp out of the more expensive stuff like MR9.

 

Is 2 hp really going to make a difference? Well, if your racing at the front maybe...

 

 

I'm currently having a Nemesis ECU installed in my Bike,(Ducati 749r). This ECU has the capability to have multiple maps installed that can be switched at the starter button. One map will be for pump gas and another will be for oxygenated race gas. The numbers I have heard are about 5 more HP on race gas. Does that make a difference? Only when I'm on the straights and the guy next to me is on a Susuki 750(750 SB) or a 1098 (open twin) classes........

He probably will still blow by you. 750 twin cannot compete on straightaway with a 750 I-4.

[Hotfoot]

First off, high octane fuel will do NOTHING for performance. High octane fuel is only meant to resist detonation in high compression motors. So unless you have milled your head or have different pistons you actually want to run the lowest octane fuel you can for your bike. Low octane fuel is more volatile and will produce more power. As long as the engine doesn't ping or knock on a lower octane fuel.

 

 

 

Real race gas is a whole other story. Fuel like VP MR9 or Ultimate 4.2 will produce more power. To get the most out of race fuels like this you should map the bike for it as they tend to make a bike run lean. These fuels produce more power because they are oxygenated, not because of the octane rating.

 

 

My ZX10 makes about 5 more HP on race gas then it does on pump gas, but it was mapped for race gas. If you mapped it for each type of fuel the difference would probably be less, maybe 3hp. On a typical race weekend I run pump gas in practice and race fuel durring the race.

 

The things is on a 600 you MIGHT get 2-3 more hp out of ultimate 4.3 or maybe as much as 5hp out of the more expensive stuff like MR9.

 

Is 2 hp really going to make a difference? Well, if your racing at the front maybe...

 

Stu,

 

This is really helpful, thanks. One point that still confuses me - isn't ultimate 4.3 a leaded race fuel, and is that OK to run in my stock bike? VP Fuel website says 4.2 is a drop in for pump gas (and isn't that all unleaded now?), but I thought running leaded fuel would damage the catalytic converter. Also, with the current available race gas, can it remain in the bike for a week or two or does it gum things up or cause any other problems if it sits in there?

 

Incidentally, in my case it isn't about needing the extra HP to be at the front of the race - it's about getting that little extra advantage over my riding buddies, on occasions where it's REALLY necessary.

 

Thanks for the info!

[Jaybird180]

First off, high octane fuel will do NOTHING for performance. High octane fuel is only meant to resist detonation in high compression motors. So unless you have milled your head or have different pistons you actually want to run the lowest octane fuel you can for your bike. Low octane fuel is more volatile and will produce more power. As long as the engine doesn't ping or knock on a lower octane fuel.

 

 

 

Real race gas is a whole other story. Fuel like VP MR9 or Ultimate 4.2 will produce more power. To get the most out of race fuels like this you should map the bike for it as they tend to make a bike run lean. These fuels produce more power because they are oxygenated, not because of the octane rating.

 

 

My ZX10 makes about 5 more HP on race gas then it does on pump gas, but it was mapped for race gas. If you mapped it for each type of fuel the difference would probably be less, maybe 3hp. On a typical race weekend I run pump gas in practice and race fuel durring the race.

 

The things is on a 600 you MIGHT get 2-3 more hp out of ultimate 4.3 or maybe as much as 5hp out of the more expensive stuff like MR9.

 

Is 2 hp really going to make a difference? Well, if your racing at the front maybe...

 

Stu,

 

This is really helpful, thanks. One point that still confuses me - isn't ultimate 4.3 a leaded race fuel, and is that OK to run in my stock bike? VP Fuel website says 4.2 is a drop in for pump gas (and isn't that all unleaded now?), but I thought running leaded fuel would damage the catalytic converter. Also, with the current available race gas, can it remain in the bike for a week or two or does it gum things up or cause any other problems if it sits in there?

 

Incidentally, in my case it isn't about needing the extra HP to be at the front of the race - it's about getting that little extra advantage over my riding buddies, on occasions where it's REALLY necessary.

 

Thanks for the info!

Since they can smell it, your bike isn't really a sleeper.

[hubbard_28]

Thanks for the great info Stu. I have no mapping or anything done to my bike except setup on the front suspension. I was going to try it out of curiosity, but now I know that there would be minimal difference.

[Cobie Fair]

Hotfoot--what are you talking, who are you kidding. You did CODERACE a few months ago, and haven't you whined about not having enough HP? Or was that another person I'm thinking of?

C

[Hotfoot]

Hotfoot--what are you talking, who are you kidding. You did CODERACE a few months ago, and haven't you whined about not having enough HP? Or was that another person I'm thinking of?

C

 

OK, so maybe it IS about being at the front of the race.

 

And YES, I AM still whining about not having enough horsepower, does that ever stop? I saw that other thread about 7lb equalling approx 1 horespower. If race gas gives you, say, 3 extra horsepower, that beats the heck out of losing 21 pounds, I'm changing my New Year's resolution!

 

And hey, how come no one answered my question about leaded fuel, is it a dumb question? Or is it just that the answers are environmentally irresponsible?