Octane Rating

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There is more gasoline in one gallon of 87 than 93 octane. That is because they use additives to increase the octane rating. I never run higher octane than specified unless it's my old truck. It's got a little higher compression than stock thanks to 140,000 miles of carbon build up.

Reflashing the computer will advance timing and may require higher octane to prevent predetonation. I reflashed my 2013 Mustang and had various tunes with various octane requirements.

Some cars can tell what octane is being used and adjust parameters accordingly. Advertised power ratings are sometimes based on premium grade fuel. I would assume the ECU on the CB is relatively simple and doesn't adapt in this manner.

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.
Interesting. I always thought gasoline was gasoline, but additives were used to differentiate octane ratings and different types of detergents based on brand (Chevron Techron for instance).

Can you explain more what different blend stocks are and how that can change octane? How does that differ versus an octane booster additive like what you buy at the parts store?

Sorry, but that's an "old wive's tale." I worked in a refinery for 33 years, and they use different blend stock material for a low octane blend as opposed to a high octane blend. "Additives" don't figure into it during the blending process, they're added at the truck loading rack.
Interesting. I always thought gasoline was gasoline, but additives were used to differentiate octane ratings and different types of detergents based on brand (Chevron Techron for instance).

Can you explain more what different blend stocks are and how that can change octane? How does that differ versus an octane booster additive like what you buy at the parts store?
I can give a little information, but my job was receiving the finished gasoline blend into storage tanks, not doing the actual blend. There were two units in the plant that made most of the gasoline blend stock: a Low Pressure CCR (low octane) and a High Pressure CCR (high octane). There are other ingredients that make up the blend such as butane, but each blend has a specific end result (87 or 93 octane) in mind when it's started, therefore they start with either low octane or high octane blend stock. A side note: refineries now shoot for a 85.5 octane number on a regular blend that will have ethanol injected into the truck at the loading rack because the ethanol brings the octane rating up to 87. That way they don't "give away" octane and they save money. As for additives that you buy at the auto parts store, they work, but you could go to Lowe's and buy a gallon to toluene (121 Octane) and get the same result. We used to make some stuff called Cumene that had a 130 octane rating.