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OT: Gasoline Choice

zappaa

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Jul 27, 2001
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Montclair NJ
Can anyone tell me if using regular gasoline in high performance cars damages the car in any way?
Who’s rented a high performance car on vacation and filled it with anything but regular when you returned it?
Why put anything but regular in a lease or rental? Or a bought car far that matter?
 
Depends upon how old the car is. Newer cars have CPU's that adjust based on the factors surrounding which gasoline is used, i.e., compression, etc. I run regular in my '98 SS, and it runs just fine.
 
I have an Audi Q7 picked it up 3 months ago. Premium or super is the gasoline that is what the manufacturer suggests. Unless you want to lose performance go with the higher grade fuel.
 
using a higher octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage, or run cleaner. However, higher octane allows engines to have higher compression ratios (for a more energetic explosion), more advanced ignition timing or forced-air induction (i.e., turbochargers or superchargers). Those engines perform best when fed premium fuel.

The flip side - putting regular gas in a "high performance" engine - will (a) usually void the warranty, (b) produce knocks in the engine and in some cases can (c) damage high performance engines.

That said--- in a rental car... who cares...
 
When I started riding motorcycles, everyone said stay away from Wawa gas. Every once in a while, I would need to stop to fuel up and I certainly noticed the difference.
 
When I started riding motorcycles, everyone said stay away from Wawa gas. Every once in a while, I would need to stop to fuel up and I certainly noticed the difference.
I was told that about LukOil gas stations.
 
Can anyone tell me if using regular gasoline in high performance cars damages the car in any way?
Who’s rented a high performance car on vacation and filled it with anything but regular when you returned it?
Why put anything but regular in a lease or rental? Or a bought car far that matter?
If you care about the car and want it to last, the best thing you can do is use “top tier” detergent gasolines in it. Stay away from cheap no-name gas at all costs ! I focus on that more than on octane. That said, most turbocharged engines are built to run on premium gas. Running regular gas in them won’t hurt the engine per se, but performance may suffer over time.

Personally I use Costco gas whenever I can. Top quality and great price.

 
As stated above, a higher performance engine typically will have a higher compression ratio (pressures) . With " regular" gasoline, the fuel and air mixtures can ignite prior to the spark plug sparking simply due to the elevated pressure. .... causing a pre-ignition situation. In this scenario, the piston is still in its compression stroke, however there is already high pressure burning Fuel/air mix, causing much higher stress on the metal parts in the piston rods, crank and other connecting rods etc, in addition to the higher temps and pressures in the combustion chamber. Higher octane gases (premium) are formulated to not ignite when only subjected to the elevated combustion pressures and temperatures. The increased stress and temperatures on your engine parts will, over time cause damage. Not sure a one time use of the lower octane fuel will create a significant issue
 
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Can anyone tell me if using regular gasoline in high performance cars damages the car in any way?
Who’s rented a high performance car on vacation and filled it with anything but regular when you returned it?
Why put anything but regular in a lease or rental? Or a bought car far that matter?

That made me laugh! Sorry for not contributing, though...
 
You’ll foul up your injectors with trash gas. Totally not worth it. Also, your high compression engine depends on high octane for maximum performance. If you don’t want to pay for premium gas, get a Honda Accord, which gets great performance on regular gas.
 
Any idea why Sunoco no longer participates as a Top Tier fuel retailer due to Covid?

It costs money to have the fuel certified. With less cars on the road it was probably eating in to the profits. Believe it or not gas is not sold at a huge profit, which is why almost all stations have some kind of convenience store or mini mart, that is where they are making their money.
 
Use high detergent like BP, Citroen and Gulf. Look for the Top Tier rating.

Exxon must have really turned their act around in the last 25 years to be considered a Top Tier brand.

I used to work summers for a pipeline company whose pipes and tanks were used to transport and store different brands of commercial gasoline as well as jet fuel for Newark. When the product is flowing in or out it is tested every few hours. Exxon gasoline looked like sludge over 80% of the time.

FWIW back then the best looking product was BP (almost clear), Mobil (before Exxon merged with it) and Sunoco (pinkish tint but clear).

Like I said though, these are my own old, unscientific observations.
 
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I have an Audi Q7 picked it up 3 months ago. Premium or super is the gasoline that is what the manufacturer suggests. Unless you want to lose performance go with the higher grade fuel.
What kind of higher performance are you looking for? I go back and forth to kids schools and activities and Whole Foods and target, so regular performance works for me. Then again, I’m not really a car guy
 
What kind of higher performance are you looking for? I go back and forth to kids schools and activities and Whole Foods and target, so regular performance works for me. Then again, I’m not really a car guy
It’s what the car dealer and online suggests you out in this car. I was going to buy a Honda after my last car a Cadillac but right before I pulled the trigger on an accord. I said to myself EH no credit card bills pay extra on the mortgage every month religiously and I make a good buck why am I getting a Honda. To each his own but I love my truck and I’m not a car guy. Unfortunately these cars need higher performance gas for all the reasons stated in this thread.
 
It’s what the car dealer and online suggests you out in this car. I was going to buy a Honda after my last car a Cadillac but right before I pulled the trigger on an accord. I said to myself EH no credit card bills pay extra on the mortgage every month religiously and I make a good buck why am I getting a Honda. To each his own but I love my truck and I’m not a car guy. Unfortunately these cars need higher performance gas for all the reasons stated in this thread.
Understood. You've earned to treat yourself. Good deal. Take the dealer's advice especially if you're keeping the car long term. I lease simply because I like having a new car every 3 years and don't want to worry about doing anything more than putting gas in it and changing the oil (for free), but I'm good with a base model Pathfinder which offers all the performance I need haha. I have no investment in the long term health of the car, so "fill it, regular, cash" rolls off my tongue as freely as "salt, pepper, ketchup".

I will say, my first car was an old Wrangler that "dieseled" any time I put anything other than premium in it. I had to supplement with carb cleaner occasionally as well. What a headache and perhaps that's why I'm looking for as little maintenance as possible now.
 
Exxon must have really turned their act around in the last 25 years to be considered a Top Tier brand.

I used to work summers for a pipeline company whose pipes and tanks were used to transport and store different brands of commercial gasoline as well as jet fuel for Newark. When the product is flowing in or out it is tested every few hours. Exxon gasoline looked like sludge over 80% of the time.

FWIW back then the best looking product was BP (almost clear), Mobil (before Exxon merged with it) and Sunoco (pinkish tint but clear).

Like I said though, these are my own old, unscientific observations.
Gasoline is comingled at the terminals. The only difference between the BP gasoline and the Mobil gasoline that goes in your tank is the brand specific additive package that is mixed in when the tanker truck picks up the load to be delivered to the gas station.
 
For Mazda, the compression ratio is 14 to 1 which is high, and the manufacturer states to use regular 87 octane. The turbo model they also recommend regular unless you want extra performance, but that extra performance only comes after going over 3 or 4 thousand rpms and the extra power isn't very much more horse power. So I do not think using regular in a modern sports car can hurt it, it just won't get extra power in the higher rpm range. But read the manual for the exact answer for a particular car.
As for gas, I don't fully buy into the Top Tier is better theory but the manufacturer of my car recommends it, and I have put nothing in my car except BP since new, from 2018.
 
Gasoline is comingled at the terminals. The only difference between the BP gasoline and the Mobil gasoline that goes in your tank is the brand specific additive package that is mixed in when the tanker truck picks up the load to be delivered to the gas station.
Comingling is inevitable but I'll tell you those pipeline companies have sheds with sinks attached directly to the manifold that they use to pull samples from. They also pull samples from the roofs of the tanks. They store those samples for a pre-determined amount of time in another shed on property. Looking at those samples is like looking at a rainbow but you can definitely see which company refines a cleaner product. The majority of samples are clear enough to see through and after a while you can identify what brand of gas is in the sample just based on it's tint. Exxon gas was neither clear or tinted. It was straight brown mud most of the time.

Again, it wasn't my job to take and analyze the sample but I stood over enough shoulders in the three summers I spent there to detect a simple pattern.

Coolest thing I ever learned there is that jet fuel is not buoyant. If you jumped off the edge of a tank into it you'd fall to the bottom just as if you jumped off the outside into the air. Always thought that was neat.
 
For almost every part of the OP I agree that you just buy cheapest gas available. Though, if on a lease, I do try to at least find good gas but even though we have high end vehicles, Range Rover, BMW, I am not doing super in them when leasing. If I have a vehicle that I have purchased, I do use premium gas and good rating.
Rentals...haha sorry but if I could piss in them, I would.

As for the performance, I am rarely over 90 and I don't race anyone from a light, so, that is not my reason ever. Engine knock and just smoother running...maybe help with years 5-10...that is more my reason.

And I have never had a dealership analyze my fuel on any warranty issues. Would be almost 100% impossible to ever pin that on you anyway. What are they going to say - "You have inferior gas in the tank" if that ever happened to me, my response is..."who the F can trust those GS owners for what they put in my tank in NJ where we don't pump our own gas. I always ask for premium" and what would they do if it is a cert pre-owned and still on warranty? You didn't even own the car for the first 3 years.
 
I would also highly recommend using a true synthetic motor oil like Mobil 1.
Agreed. Most new cars actually come with synthetic in them these days..

I have a Mazda and a Volvo and both came with synthetic.
 
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Understood. You've earned to treat yourself. Good deal. Take the dealer's advice especially if you're keeping the car long term. I lease simply because I like having a new car every 3 years and don't want to worry about doing anything more than putting gas in it and changing the oil (for free), but I'm good with a base model Pathfinder which offers all the performance I need haha. I have no investment in the long term health of the car, so "fill it, regular, cash" rolls off my tongue as freely as "salt, pepper, ketchup".

I will say, my first car was an old Wrangler that "dieseled" any time I put anything other than premium in it. I had to supplement with carb cleaner occasionally as well. What a headache and perhaps that's why I'm looking for as little maintenance as possible now.
“Carb cleaner”, LoL. You’re dating your self
 
It is all about the octane, if you put a higher octane than what is recommended the only thing you are hurting is you wallet. Putting lower octane than what is recommended MAY cause issues. Yes new cars have various sensors like a knock sensor and can make adjustments this typically takes when you are at cruising speed or a "steady" state. It is when you are in a "transient" state (like smashing the gas pedal) that you can have issues. This is because the sensors cannot react fast enough to adjust timing and spark.
 
Can anyone tell me if using regular gasoline in high performance cars damages the car in any way?
Who’s rented a high performance car on vacation and filled it with anything but regular when you returned it?
Why put anything but regular in a lease or rental? Or a bought car far that matter?

For rentals, who cares - that’s a Hertz problem.

For personal, double check your warranty. You may void it by using non spec oil and gas. Lower octanes may cause knocking in high performance vehicles and could lead to engine damage.

FWIW, Im not a car guy and this is second hand from the dealer so this could be incorrect.
 
For rentals, who cares - that’s a Hertz problem.

Reminds me of the looters and rioters who claim stealing and destruction of private property is no big deal because insurance will pay or doesn’t matter because the victim is just a rich corporation.

Welcome to America 2020.
 
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My BMW has a note at the filler tank that says "use 91 octane". I do a pretty good job of mixing tanks of Costco Premium (93) with other decent Plus (89) when not near my Costco. I would never just run regular in it.
 
11.7% of gas sold is premium grade

Premium grade accounted for more than 1 million barrels per day, around 11.7%, of all gasoline sold in the United States in June, according to the U.S. Energy Information Administration.Sep 7, 2016

Is it me or is more than 1 out of 10 cars needing premium seeming too high?

I suppose maybe some of the big pickups and SUVs might want premium. Or maybe it is that the MPG that vehicles using premium gets is much lower. Yeah.. that's probably it.
 
11.7% of gas sold is premium grade

Premium grade accounted for more than 1 million barrels per day, around 11.7%, of all gasoline sold in the United States in June, according to the U.S. Energy Information Administration.Sep 7, 2016

Is it me or is more than 1 out of 10 cars needing premium seeming too high?

I suppose maybe some of the big pickups and SUVs might want premium. Or maybe it is that the MPG that vehicles using premium gets is much lower. Yeah.. that's probably it.
almost every model from the premium brands requires 91 octane gas. there are some non-premium cars that do as well, i.e., subaru's and various VW engines
 
For rentals, who cares - that’s a Hertz problem.

For personal, double check your warranty. You may void it by using non spec oil and gas. Lower octanes may cause knocking in high performance vehicles and could lead to engine damage.

FWIW, Im not a car guy and this is second hand from the dealer so this could be incorrect.
Oil would make sense but in a state where you don't always pump your own gas, hard to prove you did not always ask for premium and maybe an attendant screwed up or did a switch on you. just saying
Reminds me of the looters and rioters who claim stealing and destruction of private property is no big deal because insurance will pay or doesn’t matter because the victim is just a rich corporation.

Welcome to America 2020.
You really can't be serious in any way. If you are, I will pray for you tonight. lol
 
You really can't be serious in any way. If you are, I will pray for you tonight. lol

Putting fuel in a car that is likely to cause damage does not seem okay simply because “it’s a rental” owned by a large company.

BTW, thanks for your insult. As a professing Christian, you are likely aware of this passage:

“Blessed are you when men hate you, and ostracize you, and insult you, and scorn your name as evil, for the sake of the Son of Man.”

Luke 6:22
 
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