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Regular fuel vs Premium fuel

To my surprise, on several occasions I’ve heard you advocate the use of regular fuel and declare the premium fuel is superfluous except where specified by manufacturer. In my personal experience, regular fuel often results in pinging, run-on, and harder starting on cold mornings. Premium seems to offer many benefits worth the price, including cleaner running. I’ve driven every kind of car from Morris Minor 1000s to Ferraris, to Buick Roadmasters, to Austin Healeys to… well, you name it. In every case, I’ve found Premium fuel to deliver a more satisfactory driving experience. Here in Canada, one can sometimes find Sunoco 94 octane fuel, and it seems to offer even more performance. Why do you claim that Premium fuel is no advantage. It is especially effective in old clunkers (Isuzu Trooper), for cold starts and hill climbing under load as well as eliminating dieseling.

If your fuel injected car suffers from run-on, then fuel octane is not even close to being your problem.
I’ve found the higher octane is sometimes required for some cars that call for regular to prevent pinging.
I’ve also found that some cars that call for regular run badly on 91+ octane.
It’s a moot issue of me now as both of my current cars require 91+ octane, and that’s what I give them.

Most newer cars have knock sensors that adjust engine timing to compensate for lower octane gas. High-compression engines from the 1960’s required premium fuel as they did not have the sophisticated electronics cars have today. If your engine is knocking on low octane fuel, I’d suggest a tune up. Your owner’s manual will list the recommended/required octane fuel.


If you want premium for your cars it is available.

If a current generation car, or truck, is designed to run on 87 octane regular (as stated in the owner’s manual or the gas filler door) then using higher octane premium is a waste of money. Such a car will not run better, it will not get better mpg, it will not be cleaner, and it will not climb hills better, it won’t last longer.

I have two vehicles that require regular and one that requires premium (91 octane or higher). The one that requires premium gets premium, the other 2 run just great on regular.

I think if you looked at even the low level scientific description of just what makes a fuel “preminum” your post would not exist.

You say yor cars are “cleaner running” I must ask you to elaborate, you also add that you have a more enjoyable driving experience, I say this is “good bang for the buck”

Can you present any basic reasoning why any of the benifits you claim exist due to the use of preminum fuel in a vehicle it is not required or even reccommended for?

The octane rating is the resistance of the gasoline to burning. The higher octane does not ignite as quickly. This prevents pre-ignition. I would think that in cold weather, the regular fuel would be an advantage, because theoretically it should ignite more quickly.

Perhaps he owns a petroleum distributorship and is trying to boost his sales of high-profit premium gasoline…

The only reason “premium” exists is because when the sale of leaded regular was BANNED, that left gas stations with an unused pump, the old “regular” pump… So they came out with the 91-92 octane “Premium Unleaded” to fill the empty shelf space…It was considered a joke at the time as the old “regular” it replaced was 90 octane…But at wholesale it only cost .04 cents a gallon more and retailers usually marked it up .08 or .09 cents. They didn’t sell much of it because for 3 or 4 years, not a single car made required it. The old 10.5-11.0 to 1 compression “Premium Fuel” cars would not run on it and then, as today, they must use 100 octane low-lead aviation gasoline…

Few motorists today have ever heard “spark knock” “ping” or “detonation”… They simply don’t know what it is, but they have been convinced they must avoid it at all costs so an amazing amount of premium priced fuel gets sold…

Not quite…Once ignited, premium burns just as “fast” as regular. Octane is a fuels resistance to SPONTANEOUS ignition caused by the heat of compression… Once ignited by a spark, they both burn with equal vigor, the flame front travels at the same speed…