Regular or High test?

I remember back in the early 1960s my grandmother using the term "ethyl" for Premium; at the time she was driving a Ford Galaxy 500 with the Thunderbird 390 V8 in it.

 

Yep, i've tried running 92 or higher octane a few times, and same results every time...truck runs like chit. Seems with 89 no difference i can tell except more expensive. With 87 my trucks just runs great.

 

I remember back in the mid 70's pulling into a gas station and filling up my street toys with 98 octane leaded premium

 

I'm 64. I can remember my dad using the term "Hi Test" when I was a kid but haven't heard that term in years.

Yes, in a modern truck using premium or 93 octane fuel can make a difference. If you read the owner's manual it DOES NOT SAY USE 87 OCTANE. It says something along the lines of "Use 87 octane or higher fuel". That means that even at high altitude where they sell 85 octane fuel don't use it. Stay with 87 octane or greater. And if you want better performance, albeit at a greater cost you can use premium.

Years ago cars were either tuned for regular or premium. If your car was tuned for premium using regular gas made a noticeable loss of performance and long term could damage the vehicle. If you had a car tuned for regular gas then using premium was a waste of money.

But today's vehicles use computers that can compensate for the type of fuel your using. And the newer the vehicle (actually the higher compression ratio, which is more common in newer engines), the bigger the difference. A 3rd gen Tacoma will see more improvement from premium than a 2nd or 1st gen. If you want to use regular 87 octane fuel in your truck it will run acceptably well. But if you want, or need a bit better performance using 93 octane will make a difference. This is most noticeable when towing or if you need better acceleration.

I used to be in the camp that said it was a waste of money. But I was wrong. I stated experimenting last summer while on a cross country trip towing a travel trailer. It made enough difference that I've used nothing but 93 octane in all of my vehicles since last July. You can't just try one tank and make any judgements. For one thing you'll have a mix of regular and premium gas until you get to about the 3rd fill-up. And it takes a little time for the engine to adjust to the different fuel. Plus if I start out towing with regular gas in my truck I'll be 200 miles down the road before I even put the better fuel in the tank. I just find it easier to keep it in there.

Where I live 93 octane is about 50 cents/gallon more expensive than regular. In addition to better performance I'm getting about 1 mpg better fuel mileage. No that doesn't offset the additional cost, I'm spending more for fuel. But the bit better fuel mileage does ease the pain some. But for me the better performance is worth the cost. I'll spend $75 for a tank of regular gas. $82 for premium just isn't that much more.

 

Just the opposite here when using 92 or higher gasoline. I'll get a couple mpg less, the truck hunts going up the same grade roads when running 87 doesn't. Plus if i look at the tail pipe tip, its all sooty black with carbon where using 87 is a light orangy tan. Idk, if this makes any difference but all our grade fuels here are 10% ethanol.

 

No. Makes no difference whatsoever. Octane is to limit pre-detonation. Anything else is marketing bull. Full stop.

I’m prepared for the onslaught.

 

We used to call things what they are. High test relates to the octane refining that was actually tested. Now octane is a mixed value to allow for blending of cheaper chemicals. “Premium” or “Super” are purely marketing terms to encourage and promote a sense that it is something better.

 

The over 80 crowd uses "Hi-test"

 

"High test" and "Ethyl" terms are known mostly by Boomers and their parents.
Back in the day Amoco's "High test" was actually unleaded and was also marketed as "White gas" - often used for camp stoves and lanterns.

I ain't there yet and I'm familiar with the term.

I remember Sunoco 260 - worked at a station that was on the road leading to a NASCAR track. Many of the drivers would fuel up for the Friday night races.
Then the owner of the station started selling Cam 2 when Sunoco went to 100% unleaded.
Loved the smell of a just started small block Chevy running 260.

 

There is absolutely no such a thing as "pre-detonation"; there is one of the following:

• Detonation:
  • Long (in relative terms) after the spark event, small pockets of end gas can combust due to local heat and pressure; this phenomena is also known as pinging.
• Preignition:
  • Prior to the spark event when there are serious mechanical issues with the engine which can cause hot spots, the intake charge can be touched off; if/when this happens to an engine it will be destroyed in as little as a few revolutions and no amount of octane will prevent it.

 

And it probably ate the C4 trans they put in it, just like the one my parents owned. My dad loved the "get-up-and-go" but hated having the car towed to the dealer every 4 months for a trans rebuild.

 

I was still pretty young the last time I saw the car but I'm almost positive it had a manual transmission; I remember always lurching forward and then getting slammed back into the seat everytime she'd shift gears.

 

Funny this should come up. I'm an LTL truck driver and at one of my deliveries this past week was a '64 Galaxie 500 2 door, white w/blue interior. Solid looking car (probably not originally from WI) with only a small bend in the grille.

 

How so? Modern cars are safer, more reliable and efficient

 

I sprinkle a bit of diesel in every now and then - like to keep my truck guessing

 

Correct. Albeit its an oft used hyphenated literary contrivance to emphasize the auto ignition hypothesis vs the end gas flame acceleration with detonation.
I’m not here to “knock” the formal definitions.

 

I did not read any of this thread, but seeing the phrase "High-Test" took me back a ways and made me smile. Thanks brother!

 

IMO, octane is a lot more complicated than most make it out to be.
RON vs MON(octane sensitivity) and from what sources each are derived(E0 vs E10) don't get enough play. ONR vs ORI as well.
This is from a Chevron paper; albeit 2010...
I believe inaudible knock is common, as shown by many members who have logged 'non catalyst damaging knock events'.

 

I only use jet fuel. Gives my the best all out performance when jumping speed bump in the Walmart parking lot.

 

My truck definitely runs better, stronger, quieter, smoother and gets better MPG on ethanol free, octane doesn't seem to make much difference though.