Why Purchase an Automobile using Premium Gasoline?

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vitaflo
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by vitaflo » Sun Oct 21, 2018 4:36 pm

Nowizard wrote:
Sun Oct 21, 2018 4:20 pm
a major reason to purchase a vehicle using premium is simple preference for a specific vehicle that may ideally require premium, but can run on regular gasoline. Stupid me, I thought that 2005 V6 Honda Accord was pretty fast, along with several policemen met on highways :happy
Tim
If it requires premium, it shouldn't be run on regular gas. There's basically 3 types of engines: Ones that require premium and can be damaged if you run on regular. Ones that recommend premium but can be run on regular at different timings with less performance. And those that are designed for regular that see no benefit in running on premium.

bhsince87
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by bhsince87 » Sun Oct 21, 2018 4:57 pm

killjoy2012 wrote:
Sun Oct 21, 2018 3:21 pm
What most of the people in this thread are missing is, that since the US government has been pushing CAFE standards higher and higher, the only way the OEMs can meet the mandatory fleet requirements is to produce an increasing number of vehicles using smaller and more efficient engines/technology, which generally means more turbocharging. There's a reason you now commonly see mid and full-sized trucks & SUVs, like the F150, with a v6 turbo option. And this is generally true across the board.

Does turbocharging add cost to the vehicle/engine? Yes. Does a turbo require premium gas? Yes. But neither really matter since the OEMs are being forced to meet CAFE standards and hopefully the increased power, torque and efficiency of the turbocharging offsets any additional cost of premium gas.

The OP's statement/hypothesis doesn't really make sense though. A turbocharged engine is going to make more power and torque than the same engine minus the forced induction... so their opinion that started this thread is generally flawed. If you don't want to pay for premium gas - fine, buy a car that doesn't require it. But one that does likely makes more power and gets better MPG (assuming you keep your foot out of it) than the same non-forced induction, at least to the point where you'd need to do the math on paying an extra 10% at the pump vs. performance that the superior engine provides.
"Does a turbo require premium gas? Yes. "


This is not always true today. My twin turbo F-150 engine states in the owners manual that it requires only octane 84 or greater.
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jharkin
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by jharkin » Sun Oct 21, 2018 5:32 pm

Jack FFR1846 wrote:
Sun Oct 21, 2018 1:59 pm
While some of the above technical explanations are truly hilarious, I'm going to stick with simply answering the OP's question.

Why people buy a car that requires premium fuel is because they like the car, like the performance and are willing to pay the extra.
These threads always get full of people that dont fully understanding the science involved making "definitive" statements. .. just like the OP assuming more octane= more power.


OP:

Octane is a rating of fuels resistance to knock, or detonation That is a function of compression ratio - run too much compression with too little octane and the fuel can spontaneously combust from the heat of compression before the spark plug fires.

https://auto.howstuffworks.com/compress ... atings.htm
https://en.wikipedia.org/wiki/Octane_rating

Counterintuitively, higher octane fuel actually has a lower energy content than low octane fuel, but engines designed to use high octane fuel usually produce more power out of a smaller displacement, so you get back more than you give up in the increased power to weight ratio.

For this reason, high compression ratio or highly boosted (turbo or super charged) engines that require super often make as much or more power than much larger engines that run on regular, significantly reducing the weight of the car or allowing you to make it smaller. The result is that you can get a large advantage in either acceleration or fuel economy (or both) for a small increase in cost. Prime example is many modern turbo charged engines in the 1.5-2.5L range make as much (sometimes more) power as old 5-7L V8s did 20 years ago and the cars are 500-1000 lb lighter because of it.. That weight savings provides enormous benefits in acceleration, handling, fuel economy AND safety.

Super unleaded costs about 10% more than regular. But if using the fuel allows you to produce 20%, 30% or 50% as much power from a smaller engine you actually end up ahead.

Now as with every question in engineering, the real story is a lot more complex, and modern computer controlled engines allow the designers all kind of tricks to stretch the limits and sometimes use regular in designs that would traditionally have needed high test.. but in general the above is true. Don't get hung up on an extra 10 cents a gallon on fuel when you are making a $30,000 purchase. Buy the vehicle that fits your need.

arsenalfan
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by arsenalfan » Sun Oct 21, 2018 5:34 pm

Not I.
Bought 3 cars that "required" 93 octane+ for best performance.
Have used regular unleaded, just fine, x 10-13 years.
Shhh...don't tell anyone.

The Wizard
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by The Wizard » Sun Oct 21, 2018 5:37 pm

killjoy2012 wrote:
Sun Oct 21, 2018 3:21 pm
...There's a reason you now commonly see mid and full-sized trucks & SUVs, like the F150, with a v6 turbo option. And this is generally true across the board.

Does turbocharging add cost to the vehicle/engine? Yes. Does a turbo require premium gas? Yes...
My 2016 F-150 with 3.5 litre turbo does not require premium gas...
Attempted new signature...

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Kenkat
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by Kenkat » Sun Oct 21, 2018 5:39 pm

Around here, premium (93) is 60 cents a gallon more than regular (87). It’s about a 25% premium for premium.

inbox788
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by inbox788 » Sun Oct 21, 2018 5:48 pm

Leesbro63 wrote:
Sun Oct 21, 2018 3:56 pm
But the Lexus RX and NX serve very similar, overlapping, market segments. Your theory that requiring premium signals a better car makes some sense, but not in this case.
While there's some overlap, they have very different competition. The NX competes with other luxury cars like the Audi Q5, BMW X3, Volvo XC60, Acura RDX and Mercedes GLC. The RX (and now RXL) also goes up against the Acura MDX, 3 row SUVs and minivans who's buyers are more sensitive to the premium fuel issue. Those that balk at the NX might go for the RAV4 (moreso than RX buyers downgrading to Highlanders). It wouldn't surprise me if they upped the Highlander higher trims and re-instituted the premium fuel recommendation or requirement on the RX.

ssquared87
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by ssquared87 » Sun Oct 21, 2018 6:35 pm

inbox788 wrote:
Sun Oct 21, 2018 3:52 pm
Leesbro63 wrote:
Sun Oct 21, 2018 2:09 pm
A few years ago when I was trying to decide between the Lexus RX and the Lexus NX, the fuel thing was part of my decision to go with the bigger vehicle (RX). Oddly, the NX requires premium but the RX does not. And even though the NX is a smaller vehicle, when you factor in the cost of premium, the cost to run both vehicles was exactly the same. True, the RX cost about $4000 more, so I'm not saying gas was the only thing. But I guess the little birdie in the back of my head was saying "if you're gonna compromise on a smaller vehicle, you are not getting any fuel savings for doing so". It's the old American-car thinking that bigger is better.

I'm surprised that Lexus doesn't make a regular-gas version of the NX. Not everyone cares about turbo-charged zip versus better fuel economy, even in a luxury vehicle.
The luxury marketing goes like this. Premium cost more so it must be better. If a car doesn't take better fuel, it must be worse than the one that does. Even if a luxury car doesn't need premium fuel, requiring premium signals that it's a better luxury car. If the buyer is willing to spend more money on better gas, they'll definitely pay more for the car. With most luxury cars, those that are willing to pay more for the car are also willing to pay more for gas, so they're not giving up a lot of sales by requiring premium fuel. You could say with the RX and a few other luxury cars that the engineering makes premium unnecessary, but I think it's more the marketing for this lot of drivers and a sufficiently large percentage who would be turned off by the higher octane and cost requirement.
It has nothing to do with marketing. The NX uses a 4 cylinder turbo while the RX uses the V6 from the Camry. They are very different designs with different requirements to run optimally.

The only marketing aspect about this is that a Lexus is just a pig with lipstick (Camry with nicer leather).

criticalmass
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by criticalmass » Sun Oct 21, 2018 6:39 pm

killjoy2012 wrote:
Sun Oct 21, 2018 3:21 pm
What most of the people in this thread are missing is, that since the US government has been pushing CAFE standards higher and higher, the only way the OEMs can meet the mandatory fleet requirements is to produce an increasing number of vehicles using smaller and more efficient engines/technology, which generally means more turbocharging. There's a reason you now commonly see mid and full-sized trucks & SUVs, like the F150, with a v6 turbo option. And this is generally true across the board.

Does turbocharging add cost to the vehicle/engine? Yes. Does a turbo require premium gas? Yes. But neither really matter since the OEMs are being forced to meet CAFE standards and hopefully the increased power, torque and efficiency of the turbocharging offsets any additional cost of premium gas.
A family member bought an Audi A4 model with a turbocharger and used regular gas in it for the next 14 years. The car was sold due to age and increasing electrical issues (Audi is a Volkswagen brand after all) and the engine was fine. Could it have gotten better mileage with Premium fuel? Maybe but it was still over 30 mph on regular, which saved 30-50 cents per gallon.

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dm200
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by dm200 » Sun Oct 21, 2018 6:47 pm

Many years ago, as I recall, there was, almost at least, a certain aspect of those who filled up with "High Test" were better than those of us who just used "regular". Using "High Test" was a certain "status symbol" -- sometimes folks would put in "High Test" even though it did no good. :sharebeer

finite_difference
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by finite_difference » Sun Oct 21, 2018 8:45 pm

kjvmartin wrote:
Sun Oct 21, 2018 3:14 pm
denovo wrote:
Sun Oct 21, 2018 12:30 pm
Nowizard wrote:
Sun Oct 21, 2018 12:28 pm
Automobiles using regular, unleaded gasoline typically, I think, get better mileage and have comparable torque and acceleration in my experience.

Oh really, please tell me any cars that use regular, unleaded that can go 0-60 in less than 4.5 seconds?
2018 Mustang GT
Also, 2018 Porsche Cayman GTS — should manage 4.4 on regular I should think. But you’ll have to buy me one so I can test ;)

Honestly, do you think most luxury car drivers will care if you can do 0-60 in 4.5 seconds or 5 or 5.5 seconds?

Unless you’re taking it to the track I don’t think one or two seconds matters. You can’t really drive like that normally, unless you enjoy getting pulled over and wearing out your tires/suspension.
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Nissanzx1
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by Nissanzx1 » Sun Oct 21, 2018 9:15 pm

I've put 100's of thousands of miles on cars that require premium. I use 87 octane, never any problem. I have two Mercedes in the garage now with 87 in the tanks. One we drove 150 miles this morning...

shunkman
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by shunkman » Sun Oct 21, 2018 9:19 pm

While we are at it, what's the best brand of oil to use?

Nissanzx1
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by Nissanzx1 » Sun Oct 21, 2018 9:23 pm

shunkman wrote:
Sun Oct 21, 2018 9:19 pm
While we are at it, what's the best brand of oil to use?
That's almost a religious question to some. I use Mobil 1 full synthetic or Walmart Super Tech Full Synthetic. The walmart oil performs very well and is only like $17 for 5 quarts ($20 full synthetic oil change).

shunkman
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by shunkman » Sun Oct 21, 2018 9:24 pm

You took my bait...

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wander
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by wander » Sun Oct 21, 2018 9:38 pm

Cars that require premium gas tend to be luxury. If you pay premium for a car, why do you think too much on paying extra for gasoline? I am driving an old Lexus and always fill it with premium gas as recommended without question. If you want to fill your car with regular, it works too.

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Kenkat
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by Kenkat » Sun Oct 21, 2018 9:41 pm

There is a distinction between premium required and premium recommended. The vast majority of modern cars will run on regular fuel, so while premium is recommended, it is typically not required. Very few cars actually require premium fuel.

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munemaker
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Re: Why Purchase an Automobile using Premium Gasoline?

Post by munemaker » Sun Oct 21, 2018 9:45 pm

If you want to buy a high performance car with a lot of horsepower, you will end up using premium gasoline.

If you have to ask why, then you would not be interested in such cars.

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Re: Why Purchase an Automobile using Premium Gasoline?

Post by LadyGeek » Sun Oct 21, 2018 9:48 pm

This thread has run its course and is locked (not productive). See: Personal Consumer Issues
Note that this subforum has a much lower threshold for locking or removing posts than the financial and investing subforums. In general, controversial, offensive, pointless, divisive or mean-spirited posts or topics may be locked, edited or deleted (with or without notice) at the discretion of the moderating staff even if they do not otherwise violate forum policies.
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