they will be making high octane gasoline

[rmmchl]

The refiners are working with the govt to develop high octane gasolines above 100 octane, because it will improve gas mileage by upwards of 20%. They should be everywhere in less than 5 years. They will phase out 87 octane.  I wonder how our pagodas would run on 110 octane gas? Any thoughts?

[JonathanB]

Even if 100 octane gas were somehow "too strong" for our 50 year-old engines, I would think one could blend it with 91 octane gas in order to achieve the optimal mix.

My understanding is that gas stations only buy two types of gas: 91 and 87 octane.  The "mid-grade" is simply a 1:1 mixture of them blended by the pump.

[Tyler S]

They run much better. You can get away with more ignition timing advance and run hotter spark plugs as well.
Also on engines that have had their head surface machined, which raises compression, the higher octane fuel is less likely to pre-ignite.

[mdsalemi]

This is interesting, but I'll believe it when I see it. Right now, in Michigan, premium fuel is about 28% more costly than regular. Even if the 20% greater fuel economy is accurate, I'm not about to pay 28% more to get a 20% boost.  Of course, I understand that if the ONLY fuel available would be 100 octane, or 110, the pricing picture might change quite a bit.

100 octane and greater fuels are available now. Sunoco 260GT (100 Octane) is available locally for about $10 per gallon. Though not legal for use as an on-road fuel, it was once common for some automotive restorers to use AvGas 100LL, (aviation fuel) locally about $7.78 per gallon.  The bottom line is octane is costly today. Very costly.

I do know that my Pagoda really does not like regular fuel, and prefers the premium. One of my other cars is a high performance Ford Taurus SHO. I've used both regular and premium in that, and without some kind of instrumented, scientific testing there's no perceptible difference in performance (thought the HP rating is best with the premium) nor in MPG. There's a a realtime fuel MPG meter and environmental conditions make more of an effect than anything else; speed, weight, weather, etc.  Thus that is always fueled with the lowest-cost gasoline available. The Pagoda is always fueled with the highest octane available at normal stations.

[JamesL]

Our "standard" unleaded is 95. Premium is 97/98 and some places sell a super premium 99 (RON)
Difference between RON, MON, and AKI
Because of the 8 to 12 octane number difference between RON and MON, the AKI shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel. This difference between RON and MON is known as the fuel's Sensitivity, and is not typically published for those countries that use the Anti-Knock Index labelling system.

[Tyler S]

Read an article somewhere about this. Cant quote it as I dont remember where but its the auto makers pushing for this. Lots of newer cars run turbos now, And higher compression. Higher octane is necessary for the engines to run properly. Was stated that its a "**** for tat" proposition. Auto makers are being forced to deliver products with better fuel economy and less emissions. With the current fuels they are at their limits of what can be developed. Higher octane rated fuel opens up opportunity for higher compression, higher turbo boost pressure engines. Which ultimately reduces polutants, gives more power, and can reduce fuel consumption. The auto makers are basically saying if you want better engines, give us better fuel.

[Shvegel]

I am pretty sure the 20 percent boost they are referring to would be the difference between an engine optimized for 87 octane and one optimized for 110 octane.  Simply adding 110 octane fuel to a properly tuned and running Pagoda will not increase it's performance or decrease it's fuel consumption.  In fact you may find a very slight decrease in performance and economy due to the slower burning fuel (higher octance = slower burning).

However if you scratch built an engine that was optimized to run on 110 octane fuel and increased compression,  changed valve timing and optimized your ignition timing etc you you realize your 20 percent increase.

We had good fuel back in the 1960's but two things got in the way.  The first is it used a lot of Tetra ethyl lead which was found to be harmful and the second is that engines running high combustion temperatures due to high compression and advanced ignition timing were found to produce high amounts of oxides of Nitrogen (NOX) which is also a reportedly bad thing.

I am sure with a lot of effort by some whiz bang chemists we can overcome the lead issue.  but I am not sure how they will overcome the high NOX issue.

[wwheeler]

High octane fuel that is street legal is available. https://vpracingfuels.com/vp-street-legal-fuel/ They also make 110 octane leaded fuel that is not street legal And no ethanol in both!

The unleaded is about $9/gal and the leaded is $8/gal locally. But you can blend with 92 pump gas to dilute the effect of ethanol if you are so lucky to have that, and reduce the cost somewhat.

From talking with an old timer who knows fuel, He says it is difficult to raise the octane much above 100 using current non-lead octane boosting technology. Using lead is easier AND cheaper to raise above 100 and why he says VP offers the 110 in leaded. I have to say that the difference between leaded and unleaded is astounding. I had pretty much forgotten that from many moons ago. The leaded evaporates so much faster and doesn't have such strong smell. Plus the shelf life of the leaded is about six years.