Is there a a BIG difference between premium and regular gas?

Question

Or is it just a marketing ploy to get you to spend more money?

Answer 1

Absolutely--the octane rating. The higher the octane rating of the gas (91 vs. 87, for example), the more resistance the gas has to combustion--and for high-compression engines, this means less likelihood of the fuel detonating prematurely and throwing off the engine's power strokes (causing the infamous "engine knock" and significant power loss). This is why high performance engines (Ferrari, Lamborghini, muscle cars etc.) are 91+ octane only.

That's the reason premium gas is so much more expensive than regular, and why most cars don't require it.

Answer 2

Neither. Premium gas detonates more SLOWLY than regular. Most cars only need regular. But a car with a high compression engine needs a fuel that won't ignite too soon: preignition causes"knocking" and power loss.
If the fuel ignites before the piston reaches the top of it's stroke, it drives the piston the wrong way for an instant. This "knocking," is rough on the engine.
In the old days they had a lever to "retard the spark,"
actually make the spark a little later in the cycle.
Octane is the standard molecule used for rating. Some molecules are smaller, like hexane, and ignite quicker. Some are larger and more complex, and ignite more slowly, "Higher octane."
Premium is higher octane.
Few cars need it.
Most do not understand this, and think "premium=more power."

Answer 3

Yes. Regular gas (in Texas) is 89 octane, mid-grade is 91, and premium is (usually) 93. A car designed to run on unleaded regular will not run any better on a higher "grade" of gas. The higher octanes have to do with compression ratios, and when a gasoline is compressed by higher compression ratios it needs a retarder to prevent pre-igniton. That is, igniting like diesel, from compresson heat rather than by the spark plug.

Many cars that are designed to use premium, like the Cadillac Northstar and BMW and other high performance engines, have computer-controllers that sense pre-ignition and de-tune the spark advance to take care of it. I use mid-grade in my BMW 7 series and NEVER have I heard a pre-ig knock.

There is absolutely no more power in premium than regular. The difference is that it is formulated to stay gaseous at higher pressures than regular. In theory, regular would be superior to premium because it burns a tad slower -- thereby giving the piston more push than sock. But you'd never prove it on a dynamometer, the difference being so miniscule.

Answer 4

it is not a ploy the higher the octain the cleaner the car runs and the most power you will get from your car. the lead count has nothing to do with anything. helixburger are you a mechanic b/c i am and i also do performance tuning so i do not think you have any idea as to what you are talking about. why do you think bmw's pochses and other high performance cars use it. Put low grade in your car then put high grade in it the next time you fill up and look at the difference

Answer 5

Yes, there is a difference, in theory the premium 92 octane runs cooler and improves performance and milage beause it burns slower, and is more oxygenated. Regular burns faster, has low performance and little oxygen to help milage, but is cheaper. If you have high performance cars then premium is a must, regular can burn up your valves if you dont.

Answer 6

if you want want a good grade of gas,get plus.its a mixture of premium and regular.supreme just for the hell of it is wasting money.regular gasoline is good for any wehicle except the mnetioned high compression engines in the racing circuit.id stick to regular.just buy from the top 3 oil companies and you're getting the best.exxon/mobile,shell macro,and chevron/texaco.you'll be fine.

Answer 7

regular gas is 95 Octane with lead in it (very low amount), but premium is 98 Octane and supposedly lead free, so Yes I think its a Hoax

Answer 8

2 element is large difference. First is many times the price. correct type is many times somewhat larger the commonly used. second is the octane variety. correct type has a larger octane variety than commonly used. in case your automobile is lower than assure and it says to apply a particular gasoline you probable could use it because in the adventure that they could teach you used a diverse type it would want to void your assure. probable received't do any damage on your engine, would no longer have the zip it has on correct type or it would make somewhat noise. some engines run better on correct type and others run ok on commonly used.