Home Forums Hunting & Shooting Hunter's Campfire Cars that require premium gas

By the time you (or the knock sensor) "hears" preignition/detonation noise, the engine has been running on the ragged edge of damage for quite some time. Premium gas has the slowest burning rate of the three commonly available grades of gasoline, which acts like slow-burning "magnum" smokeless powder. Running regular gas in a "premium-only" engine is like using Bullseye powder in a 7MM Magnum rifle cartridge. Adding 5% Diesel fuel to mid grade gas increases the specific gravity of the fuel and slows down the burn rate. Pump one gallon of Diesel first, and top off with 19 gallons of midgrade- - - -saves money and prevents engine damage. Half a gallon of Diesel to 10 gallons of gas works OK, too. I once had documentation on 200+ dyno runs on various types of engines we built in the high school auto mechanics program I taught for 20+ years to prove that point.

I have a Lexus NX200t. I can't see any difference between 87 octane and 93. So I use 87. The dealer said that was OK but I might get a little more mileage with 93.

Good post

U ain't got Maverick ?

Eth free clear at them

https://www.maverik.com/

I have buily many motors. Drag raced for many years. Been through a couple years of auto tech. Trust me, high compression engines deserve high octane fuel. Dont cheap out. The modern computer is a pretty cool device and can keep an engine from blowing, but its not fool proof. And once again, the engine will lose horsepower and most likely fuel mileage by running 87. Dyno proved this in a 15 camaro i had. The computer had a chit fuel table built in when someone foolishly uses 87. Maajor loss in power

My wife had a 2011 RX350 and I am pretty sure high test was “preferred” which we lived by for the most part. We put 175K on it without issue. Her 2019 Infiniti QX60 requires high test so that is what we use too. If you buy the IS250, you need to feed it the proper fuel.

My FIL has an Acura that requires high test. He's put nearly 200K on it with regular. He also barely drives the speed limit. But he told me he'll never put premium in it. Can't argue with his success.

Do you have to over-complicate decisions??

It's really very simple: If you don't want to pay for premium octane gas don't buy a vehicle that says to use premium octane gas.

The gents that own cars that require premium fuel and want to save a few bucks by running regular, go right ahead. It’s your engine. Most cars will tolerate it under most driving conditions, but do your own research, and not least, keep a record of fuel usage. You’ll use more of the cheap stuff, and get less performance while doing it. Different additive blends in premium vs regular may also mean more carbon buildup in HPDI engines running regular fuel, never a good thing for performance and economy.

Like this, mine was a 63 SuperSport Midnight blue poly.

You can't tune the need for high octane out of a modern engine, and could only
marginally do so in old ones.

You took advance out to keep it from knocking, but that was probably because
you were running a lot of advance. If you had high compression, retarding timing enough to eliminate knock was going to leave you with a bad tune.



7mm.
Ethanol has its commonly known problems, octane isn't one of those.
Ethanol raises octane a bunch. The Demon 170 100hp Dodge makes requires E85
to get the 1000hp. It can't do it on "normal" gas.
But, the gas we buy won't have higher than listed octane. The boosters in the
additive package all gas gets are expensive. The gas from the refineries has a lower
octane, calculated so that the ethanol brings it up to the claimed number.

When we first went the ethanol blend, the 93 in the system was still 93,
when it was loaded at the rack their would be some 87 mixed in to drop the octane to 93. Sheets uses the same principle for the cheap ass 91 they sell as premium.
Can't remember the amount, but it's line 15% 87. Good money for them, selling 87
for fifty cents extra. And few customers realize that they aren't getting what they think they are paying for

.

Don't look like a 63.

Dunno. All I know is that the premium coming off the tank farm in Poky is all ethanol free.

1966 Super Sports had the wrap around tail lights.

what happened after 175K ?

I have 2009 RX350

65 Impala SS's had round tail lights and the wrap around trim... i think? Evening Orchid was a one year only(1965) color, and very rare...

similar has probably already been set here. but I have an 08 Dodge 2500 with a 5.7 hemi somewhere in the book and under the hood it recommends premium fuel of 90 some octane I don't remember exactly but it runs just fine on 87. if you put the higher octane in it does run better and get about one and a half to 2 mi to the gallon better and definitely pulls a load better. but the fuel mileage alone generally does not cover the extra cost but it gets close. if I know I'm going to be pulling a lot with the truck I start putting higher octane fuel in a tank so ahead of where I'm going to use the truck under a heavier load.

Octane booster is a scam. A typical bottle will raise the octane in a tank of gas by a point or two. That doesn’t mean it turns 87 into 89.

It means it turns 87 into 87.2, you’d need a five gallon bucket of octane booster to make a meaningful difference

Then I apologize.

I do like that you at least at it you’re a cheap ass. 😂😂 most won’t admit it.

Wifeys Accura runs on mid grade, can’t use the cheap stuff

I run premium in four of my six cars, two are 70's "muscle cars" and two are a Porsche and an Audi, both turbocharged. They will all see premium fuel.