Racing Fuel

[RacingJake]

I used VP 110 and the bike ran good, then I ran some 103 VP and the bike ran alittle better by a few tenths. Have'nt did a compression test when the bike was hot at the track, but a cold compression check is at 200 psi on each cylinder. I'm at 13-5 to 1 with G4 cams.

What do you think.

Jake

 

[Anonymous]

The higher the compression, you would want to run higher octane. I run C12 in my GS750 and was told that it was about 106 octane.

 

[RacingJake]

But if you run to high of an octan you will loose power. I'm trying to find that sweet spot between not pinging and just the right amount of octan.

Made 12 runs with 103 and did'nt have any pinging at 34 degrees of timing, pulled the plugs and they looked good with no spots on the electrode.

With my total loss system the bike started everytime without problems even when it was hot and I was making back to back runs, sometimes just a few minutes apart.

I would jumper it to my truck battery and and let it run for 5 mins to charge the battery after I made 5 runs, cause that's when my air shifter ran out of air and need a recharge too.

 

[Anonymous]

Yes, that is true about finding the ideal "sweet spot"!

 

[Hoomgar]

The higher the compression, you would want to run higher octane. I run C12 in my GS750 and was told that it was about 106 octane.

The C12 we get here is rated at 108 octane.
6 bucks a gallon.

 

[Anonymous]

Yep, that's the stuff. $6.00 a gallon here too, with a 5 gallon minimum purchase!

 

[RacingJake]

Yep, that's the stuff. $6.00 a gallon here too, with a 5 gallon minimum purchase!

5 gallons will only last me 2 nights at the track.

Maybe I should convert my bike to run on Popane 8O

 

[Hoomgar]

Kero

AKA Jet fuel


Burn that and you'll be runnin cheap

 

[cbxchris]

Jake if you ever start to run nitrous check out sunoco pro mod fuel for cars. Its made to run that combo. It used to really work great with a turbo on nitrous. It had a almost unheard of octane rating....can`t remember for sure but in the 120`s.

 

[redliner1973]

Go Buy you a gallon can of toluene. mix with gas until it's right. Much cheaper than 'race gas' and is only one molecule away from gas anyhow. Plus it cleans oh so good. :twisted:

 

[lecroy]

Re: Racing Fuel

I used VP 110 and the bike ran good, then I ran some 103 VP and the bike ran alittle better by a few tenths. Have'nt did a compression test when the bike was hot at the track, but a cold compression check is at 200 psi on each cylinder. I'm at 13-5 to 1 with G4 cams.

What do you think.

Jake

I gave up on gasoline after melting one of my engines. I lost the whole top end and a crank. Methanol is better. Lower BTU,but at twice the F/A the power is a bit higher. The big advantage is how stable it is under high pressures. On the down side, it is VERY corrosive and needs to be flushed. It may be hardware to come by. Storage is a bit of a problem in that you need to keep it sealed or it will soak up water from the air and it's hard to make any power on water. :roll: :roll:

Conversion on your bike may be simple? You may need all new seals that are compatable. The shutoff valve for the float may need to be changed to allow higher flow. The gas tank will need to be changed to allow for more fuel, maybe you could weld in some Pingle petcocks? Ignition timing need to be changed. And of course you need to change the main jets. Because your just racing the bike, you may be able to get enough flow from the idle circuit but even if you can't it's not a big deal. You never idle or run mid range anyway. :twisted:

You keep playing and I may have to take you up on that $100 race you first offered! Good luck and keep us posted. Your making some great progress!

 

[Anonymous]

Methanol is better. Lower BTU,but at twice the F/A the power is a bit higher. The big advantage is how stable it is under high pressures.

And jetting is easier, because it has a bigger sweet spot and power is good until you are quite rich. Not nearly as finicky as gasoline. On a track only bike, it does have merit.

Mark

 

[Richie]

for nitrous use VP C-16 its $8.50 a gallon, runs great in our pro mod style suzuki,
Richie

 

[cbxchris]

Yeap that sunoco fuel was very dry also and your complete system had to be flushed after every race. I would run marvel mystery oil in regualr racing fuel through her at the track before leaving and fog the cylinders.

 

[Anonymous]

hows avgas 100LL? meaning a true 100 octane low lead. im running that in mine at the moment cause I work on small aircraft and had a gas can of it needing to be used, then again all im doing is blasting around the hangers till I get my liscence and put some insurance on it

 

[Robert Corrie]

You beat me to it. I was going to say go with Avgas.Been usung it for years in my 1150. The "Low Lead" is a misnomer though. Its got ALOT off lead, (more than leaded street gas had) just not as much as it used to have 20 or 30 years ago.I think the lead is to help boost octane and help lube the valve train.

 

[Anonymous]

You beat me to it. I was going to say go with Avgas.Been usung it for years in my 1150. The "Low Lead" is a misnomer though. Its got ALOT off lead, (more than leaded street gas had) just not as much as it used to have 20 or 30 years ago.

not sure how much lead it has, but you are right its just a lower amount then it used to have.

I think the lead is to help boost octane and help lube the valve train.

aviation fuel does not use aditives to boost octane level. lead in the fuel is for valve train lube, and some other stuff I forget. I think it has something to do with heat retention in the motor. I havn't really got into that yet but I will ask my boss on monday as he has been flying for 25-30 years(former CF-104 pilot for the canadian armed forces)

 

[Anonymous]

i just found out my buddy puts Union 76 race gas 105 i think, about once a month in his F4i, is this really helping or no??