i have a car that recommends high octane gas. Prices now a days are too high and use 87 octane. Manual says 93. will i be ok?

http://ricksfreeautorepairadvice.com/wrong-octane-fuel-in-car/

I was active in a Volvo forum where the question came up: does the loss in fuel economy with regular in a premium engine outweigh the higher cost of premium? A bunch of people tried it out, checking fuel economy and prices with a tank of regular and a tank of premium. Everybody who tested the difference found they paid less per mile with premium.

No. You'll get severe pinging due to pre-detonation and will damage the engine and exhaust components.

High compression engines require high octane fuel. If cost is that big an issue, just use an octane boost additive - you can buy flats of them at Walmart for cheap.

It if *recommends* 93 octane and you use 87, you'll get less power and less fuel economy(sometimes to the point where you're fiscally no better off), but no damage will be done. If it *requires* 93 octane, then you will run the risk of potential engine damage.

I suggest that you do some research into octane booster and what their definition of a "point" and "octane level" is. If a bottle of octane booster claims to raise octane by 8 points for example. It's not going to turn 87 octane into 95 octane (this is a common misconception). But rather 87.8 octane. This is why octane boosters are practically worthless when you're dealing with fuel quantities in the 15-20 gallon range that you would find on a typical car.

If you assume that the AVERAGE American driver uses about 20 gallons of gasoline a week. The price difference between 20 gallons of regular grade (87 octane) gasoline and premium grade (91 octane) is about $4.

That Starbucks Half-caff Grande Mocha Latte that you swill down every morning costs at least $5.

Can you afford the price of ONE cup of coffee to fill your car with the proper fuel, Sparky? You'll get better performance AND better fuel mileage if you use premium gasoline.

After the motor is at operating temperature find a big hill and accelerated fast up the hill. If you hear a metallic sound like popcorn popping that's called pining and will ruin the motor. Try the next higher octane rated gasoline like 89 octane and see if it still pings up the hill. If the pinging stops the octane gas you are using at the time is okay.

No, not OK if the engine requires high octane. I blew up a high octane engine using low octane fuel once. It would help to know what car you have.

Use high octane and drive less.

maybe, maybe not, add an octane booster if you're worried.

Engine computers (ECU) in modern vehicles automatically adjust fuel mixture and spark advance based on an anti-knock sensor and other sensors. You will get less power and fuel mileage with regular fuel. Unless you are doing competition driving you might at least consider a mid-grade which I often do in the winter with some vehicles.

But if a vehicle does not recommend premium fuel there is no advantage in using it. Lower compression engines cannot take advantage of the slower burning of higher octane fuels, so it would be wasted out the exhaust.