Racing fuel
- Thread starter JackFast
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Hayabusa Fury
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Where was this?
Draco1340
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Yup.
In fact you will actually go faster with 87 octane. You want to run as low an octane rating as you can without detonation. To run 100 or more you would have to advance the ignition to compensate for such a slow burn. Probably the best fuel at the track or the dyno is MR9 at 87 ocatane, and if your are mapped for it is good for an extra ~10 HP. MRX01 is good as well at 90 octane. Both are expensive and tough to get. I would recomend good old 87 pump gas.
Gen1 bikes are set for 89 Octane (r+m) Gen2 is 91
octane has nothing to do with burn rates/speed/heat output.. the ONLY thing octane indicates is a fuels resistance to ignition. (short answer)
thermal output (identical)
burn speed (identical for all practical purposes)....
there are "oxygenated" fuels available at some tracks that will increase power output. As the fuel burns, it releases captive oxygen and allows a fuller fuel burn and so more can be added.. (nitrous does the same thing)
The oxidizers used "can" be harmful to many fuel system components btw..
The only way your bike will go faster is because the weight of the money you spent out of your pocket will lighten the bike...
octane has nothing to do with burn rates/speed/heat output.. the ONLY thing octane indicates is a fuels resistance to ignition. (short answer)
thermal output (identical)
burn speed (identical for all practical purposes)....
there are "oxygenated" fuels available at some tracks that will increase power output. As the fuel burns, it releases captive oxygen and allows a fuller fuel burn and so more can be added.. (nitrous does the same thing)
The oxidizers used "can" be harmful to many fuel system components btw..
The only way your bike will go faster is because the weight of the money you spent out of your pocket will lighten the bike...
He posted in the '08 forum...I think he has a Gen2 and they need 90 min. You should not run 87 in a Gen2 Busa
hmm could be but this is really common in AZ in places.. Parker Strip or other waterways where we ran blown gas or other hi perf motors all the time had Sunoco/Torco racing fuels along with Methanol all the time...
We ran 100 LL octane AvGas pretty regular too without any problems.. AvGas is "highly volatile" however (evaporates very fast) and so can present some vapor issues. Some debates over the use of avgas but the composition is not the different from regular gas (except it had one very important additive "lead")
If you want to make power with race fuel, get a race fuel with high oxygen in it.
proud dad
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Cam 2 purple worked REAL good in the circle track car $18 for 5 gal. back in 92[115 octane].Switched to VP racing fuels [108 octane]it was only 2 bucks a gal then.That engine run like crap with 93.
You know what I'm talking about,roll a cylinder to TDC and the dome sticks up much higher than the block........
you can absolutely see ET differences in fuels
The issue is not BTU output of the fuel, it is the fuels ability to burn... higher octane fuels require higher compression ratios and higher static pressures to ignite and burn correctly.. conversely by retarding the timing on many higher compression ratio motors, you can run lower octane fuels.
As timing is retarded, the burn is started later in the compression stroke, there is less heat to deal with in the combustion chamber as the motor approaches and goes past TDC.. This keeps the secondary flame front from propagating.. (the noise you hear are the 2 flame fronts meeting inside the motor typically, ouch) Water injection can help a ton here btw...
And yes, piston/dome/combustion chamber design has a lot to do with how cheap a fuel you can run (octane and $$ run together).. Also, better cooling systems result in lower octane requirements..
Dyno and time slips are a culmination of all the variables that go into an engine, fuel is only one of them and regardless of what fuel you run, you need to do your tuning to that fuel.. Cars have the ability to tune to either grade in many cases..
If the maker asks for 91 octane in a motor, you would be foolhardy to run less and then lean on the motor at all... detonation can make a motor put out more power (pressures surge is around 10X normal) anyway, I do know that a national event team has done extensive testing on 89-105 octane fuels on a stock Gen2 busa and the ET's did not indicate much difference until they hit around 96 octane.. (the bike slowed down in stock tune)
They bumped a bit more mag into the bike and the 60' showed some help but the big end died by and equal amount.. (time for timing retard)
Anyway, for a guy running on the street, run the fuel the maker wants... just that simple..
Cam 2 purple worked REAL good in the circle track car $18 for 5 gal. back in 92[115 octane].Switched to VP racing fuels [108 octane]it was only 2 bucks a gal then.That engine run like crap with 93.
You know what I'm talking about,roll a cylinder to TDC and the dome sticks up much higher than the block........
proud dad
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our compression wasn't that high,after all it was the stock class.....Cam 2 purple worked REAL good in the circle track car $18 for 5 gal. back in 92[115 octane].Switched to VP racing fuels [108 octane]it was only 2 bucks a gal then.That engine run like crap with 93.
You know what I'm talking about,roll a cylinder to TDC and the dome sticks up much higher than the block........
think I know the pistons you are talking about ...
our blower motors were mostly flat top or dished however... now you wanna see one of our alky motor pistons? This is similar (we had the wrist pin lowered by .100)and then fly cut the valve pockets another .125" effective ration was 15.5 to 1
I'm at 13.2:1 compression.
We mapped my bike with Sunoco 260 GT Plus Unleaded racing fuel. It has 5% oxygen content, 99 Motor octane, 109 Research octane, 104 R+M/2. It made .5 hp more at peak and in places 2-4 hp more with 91 octane pump gas and almost exactly the same A/F. I run the race gas for the extra assurance against detonation and run the 260+ at the track.
Leave the 110 alone in a stock compression bike. If you want more power on the dyno or track tune it with MR9. It is some nasty stuff, don't leave it in the bike.
Sunoco 260 GT Plus
We mapped my bike with Sunoco 260 GT Plus Unleaded racing fuel. It has 5% oxygen content, 99 Motor octane, 109 Research octane, 104 R+M/2. It made .5 hp more at peak and in places 2-4 hp more with 91 octane pump gas and almost exactly the same A/F. I run the race gas for the extra assurance against detonation and run the 260+ at the track.
Leave the 110 alone in a stock compression bike. If you want more power on the dyno or track tune it with MR9. It is some nasty stuff, don't leave it in the bike.
Sunoco 260 GT Plus
jefro
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Hey guys, let me give you a heads up. If you're considering running an oxygenated fuel such as MR9, use extreme care! Alot of these fuels are extremely toxic and/or carcinogenic. Avoid contact with skin and breathing of fumes. A couple years ago I tried MR8(107 motor octane vs. 87 motor octane of MR9)in my 1000cc prostock sled and had it running for a minute or so at a time in the garage(doors open) while setting up the lowend on the Lectron carbs and ended up sick as a dog for 3 or 4 days. Nasty stuff! Picked up just under a tenth in ET but no MPH in 1/8 mile but wasn't worth the drawbacks, IMO.
ToXSicK RoCKeT
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WOW....... i think thats the smoothest A/F #'s i seen yet on these bikes
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