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Discussion Starter #1
OK i'm going to use race fuel for a few days when doin some waterX so i would like to know what jets to run at. I'm going from reg pump to 110, just want to know what you racers jet at for 0-3000ft and temps around 30-50F

Thanks
Chris

By the way i'm running 340's right now on 93octane.
 

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I beleive you can go down to 250-260's. All depends on how long of a distance you are going.
 

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Better yet,
What do you plan getting by running race gas? Have you modded the motor or where you having detonation problems before? Advanced the timing? Shaved head?
 

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Discussion Starter #5
'01 Pro-X440 Has a timing switch on it to run race fuel, and i want it to run good because i will be doing some water crossing and i want all the power i can squeeze out of it, my buddy was telling me that this sled/motor likes the different fuel and you can notice a little difference. The temp will be max of 47F the day i ride, and i will be going all day long. I also have a timing box under my cowl to adjust what fuel i'm running and how i want the sled to run. A-G is the timing box under the cowl. D is stock for all fuels then A is +3 and G is -3
 

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Originally posted by trailburner@Mar 22 2004, 11:54 AM
If you fing yourself jetting down on race fuel that means you didn't need the race fuel in the first place.
huh? jet size has no part in octane requirement. i have a modded machz, trail porting, pipes,reeds, bored carbs, and had to jet down from my stock(with these mods they were 420's) to 360's when i added a 16.2:1 c.r. dome head and race fuel.your telling me i can run pump gas or 420's and not have troubles with this head?i dont think so.
 

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Really depends on the fuel. We have to run oxygenated race in the bikes sometimes., you jet UP or burn down.

I know guys running the small domes on thier 440 doo's on av and seem to be getting away with it?
 

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Ballsout 1 says.... if ya havent changed anything, dont mess with the octane... if your sled runs best with the jets you got at say 0, take one jet out, ie 230to 220 for every 20`. on a different note to reply to whomever, there are times due to whatever changes have been done that more octane is actually reqiured, and depending on the fuel you may actually have to jet down a couple of sizes running the good stuff (if you need it) to keep the exauhst temps high enough. Race gas burns sorta cool and controlled so if runnin the good stuff jet down, but only run the good stuff if you have to. Thers gonna be alot of interpetation on this... if ya throw in the race gas (with no mods) ya can jet down a easy 3... but the thing is if you dont need the gas you`ll break even in power (dont jet ya lose for sure) if ya need the octane cuase ya twisted your timing or you added 20lbs of compression use the race gas but ya still might have to jet down to get your pipe workin.good luck dude.
 
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