I run Renegade 110 that I’m able to get at the pump for 10 bucks a gallon. Works well for my application (shifter)
So you get more power at a lower octane?
Often heard octane rating doesnt matter that much with 2 strokes.
The guys in Calgary run 91 octane in their VLR’s and are saying they have no issues. I guess we will soon find out!
Higher octane does not produce more power. That’s a street myth.
Chances are the car was running EFI with knock sensors and was able to add ignition advance due to the higher octane. The fuel itself won’t add power.
Your kart of course is carbed with an analogic ignition… so at the least you would have to change ignition advance to match the octane rating if you bump it up enough points. That said, you may or may not pick up performance, it’s hard to say with so many variables and the fact that we tend to overrev kart engines past peak power and ignition advance can impede this.
I don’t know but would guess lower timing with lower octane fuel would be a good idea? No?
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Would you rather…
93 pump gas with 10% ethanol
or
93 Pump gas ethanol free
The gasoline with 10% ethanol. It’ll make more power - ethanol is an oxygen carrier.
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Ethanol has roughly 30% less energy per unit volume than gasoline. Also, are the seals in a 2-stroke kart engine compatible with ethanol?
Since we lost access to LL AvGas in 2019, many of us running long circuit in Australia (with engines at the limit, particularly long stretches of WOT) have used Elf 102 (at circa US$3.25 per litre). In the case of the CR125 (running as a Stock Honda), this has not been without problems in that class (many seizes and detonation issues). I’ve gone from a typical 175 to 182 main jet range to a min 200 (no seizes in my case before the main jet shift, but I dusted a cylinder due to detonation). In contrast, my IAME 175 Supershifter (Euro version) is perfectly happy with our 98 (I generally use BP Ultimate), whether sprint or long/road circuit.
Yes, but roughly 10% more energy released per unit of air consumed. Your fuel pump will have no problem keeping up with a bigger jet.
What about seals? Are ethanol-compatible seals standard in kart engines?
Yes. European pump gas has had ethanol in it for more than a decade.
If I have to deliver more fuel, then that means I’m burning more for the same amount of work done. What is the net energy where we have 10% more output per unit air, but 30% less capacity per unit fluid volume? If I have to increase feed through the carburetor, then that seems like increased fuel consumption for the same workload owed to a net negative energy yield.
From my observations, and knowing a few people running there, I don’t know if I’d completely agree with that.
Rebuild times and/or performance drop-off from the engines (fresh vs. an engine with more than a couple hours on them) seems to be worse than when running the VLR on a higher octane race fuel.