Super Jet can i run 93 octane,

[txsuperjetfreak96]

ive go 96 sj, 701 b pipe, carbon tech reeds, msd enhancer ignition,12/20 skat, ada girdled head 33cc domes, running 180 psi compression, ive been running 90 octane would i b safe bumping it up to 93 octane and also should i stick with 50:1 mix ratio.

 

[jetfest]

If ur getting away with 90 93 will work better or be safer if anything

 

[Matt_E]

How will 93 work better if it runs fine on 90? :dunno:

I agree that it would be safer.

 

[Penken]

isnt 90 kinda low for running 33cc domes? doesnt ada say a 100 octane for 33cc?

 

[txsuperjetfreak96]

yeah they do but they do there tests at sea level im almost 3,000 ft above sealevel, so my compression is 180 psi per cylinder, the higher in sealevel youll actually lose 7psi per every 1,000 ft u go up in sea level, so if i was to take my ski somewhere sea level ill prob gain psi and prob have to run way higher octane. i actually got the head from jetmaniac, and hes from florida and he said he was running 93 octane with this head at daytona. so that kinda confusses me. i dont really understand the whole octane and compression thing, i think the higher octane u run will actually make your ski run cooler, and not have to work as hard. maybe someone can school me on this.

 

[orangefinger]

We run our skis with 91 at approx 5500 Feet with 33cc domes, our compression shows 180 PSI m these engines are ported and not stock bore, when we are at sea level or close
too ( Havasu ) we swap to 35cc domes which then are also 180 PSI with 91 octance, this applies to our engines we have been running without problems for the last 4 years.

 

[donteatdirt]

Higher octane gas has a higher flash point if you will or the point in which it will spontaneously com-bust the deal with higher compression is that it generates more heat and more heat means higher running temps, so if you run lower octane gas with higher heat generated from more compression chances are you will get detonation or pre-ignition and run in to big problems down the road. You could maybe get away with if you where in a bind but I wouldn't run it all the time.

 

[Heelz23]

is 87 okay for a stock 701?

 

[ajmps1]

just run super, you will run cleaner, motor will live longer, and, in the end wont save any money.

 

[Matt_E]

just run super, you will run cleaner, motor will live longer,

How?

 

[donteatdirt]

87 is fine in a stock ski.

 

[JPCharmin]

im in houston bro and everyone runs super with 35cc domes.. more importantly i would recommend running 40:1 in your premix

 

[sethrrogers]

I have a 701 w/ 33cc domes, ada girdled head, b- pipe, msd enhancer, dual cooling, ported etc etc.. I live in charlotte nc... I always run 93 with a good synthetic oil. My question is this... It gets warm here and so does the water temps.. I ride surf occasionally so in any environment im not far off sea level. At any point would it be smart to step up to say 100 octane or just switch to 35cc domes when headed to the surf or warmer days???

 

[95FX1]

higher the better!!!

i save up my pennies to get the leaded 110 (CAM 2) that about 20min away from my house....i run the 110 in ALL my toys when i can afford it....the difference is deff noticable
my motorcycles luv it best

 

[txsuperjetfreak96]

yeah jp i was down in houston last summer, had my 33 cc domes in running 93 octane with an octane booster, and i was running 200 psi compression with no problems, been runnin 93 octane, at 185 psi compression for almost 2 yrs no issues yet, and it runs supper strong.

 

[ajmps1]

the motor should run cooler on higher octane, which should reduce wear

 

[mjkammes]

run super pump gas its only a few cents more

 

[jamesgunter68]

Higher octane gas has a higher flash point if you will or the point in which it will spontaneously com-bust the deal with higher compression is that it generates more heat and more heat means higher running temps, so if you run lower octane gas with higher heat generated from more compression chances are you will get detonation or pre-ignition and run in to big problems down the road. You could maybe get away with if you where in a bind but I wouldn't run it all the time.

Like he said. The higher the octane the harder the fuel is to spark and combustion to take place
with you're set up try the different fuels and see if they benefit any better than the last
the higher octanes are made to withstand the heat and pressure inside the cylinder so that pre-ignition doesn't take pplace once you get pre-ignition the fuel on the upstroke will collide with the fuel ignited from the spark plug and that leads to detonation which will destroy your motor very quick
if you've been running 90 octane this long then you should be fine
if you can, get a borescope or little camera to look inside your cylinders for wear
hopefully that helps a little

 

[powerhouseperformance]

The most optimal fuel you can run is a fuel that is JUST enough octane to not detonate in your particular engine setup. If you have a totally stock ski chances are it will make the most hp on 87 and continually lose hp as the octane is increased because the fuel burns slower the higher the octane number. I always laugh when I hear guys talk about how they added race gas to their bike, quad, ect and it gained tons of power lol.

 

[MileHighJSC]

yeah they do but they do there tests at sea level im almost 3,000 ft above sealevel, so my compression is 180 psi per cylinder, the higher in sealevel youll actually lose 7psi per every 1,000 ft u go up in sea level, so if i was to take my ski somewhere sea level ill prob gain psi and prob have to run way higher octane. i actually got the head from jetmaniac, and hes from florida and he said he was running 93 octane with this head at daytona. so that kinda confusses me. i dont really understand the whole octane and compression thing, i think the higher octane u run will actually make your ski run cooler, and not have to work as hard. maybe someone can school me on this.

ADA recommendations are conservative, they want your motor to be very safe and not blow up. Any time you are able to lower motor temps you are able to slightly push the limits of Compression. Running Duel cooling, running in cooler water temps, running in cooler ambient air, no WOT runs will all help with Pre-ign,Deto. Cool in-coming water has an increased effect because of EGT temps. (cooler exhaust mani) I have run triple cooling (2 in mani, 1 to the head pipe) Every little bit has a impact on what you can get away with. There are so many small variables, like how your water routing is, how much water injection, carb tuning.
Compression seen on the gauge and true compression are not the same thing. On a heavily ported motor with raised port timing,you may have to go to a 30cc or smaller head to see 180psi on a gauge, but this does not mean you can run the same fuel as stock porting 35cc motor that shows 180 on the gauge. If you have run this set up for two years, then it is probably safe. On the other hand you could also be on the raged edge. In that case a load of sub par fuel from your local fuel station with warm water on a hot summer day, Racing your buddy at WTO could spell trouble. Hope this helps.