My New Car
- Thread starter Esco!
- Start date
danmand said:
Zoze germans haf vays ouf makink you use premium.
Drive a Range Rover instead, English and friendly.
Give the man a prize.smiley1437 said:
The first correct answer.
Premium gas does NOT give you any better mileage, or any cleaner combustion, all it does is prevent knock, which allows your engine to perform as designed.
The notion that the car companies are in bed with the oil companies is completely opposite. If anything, the car companies are PISSED OFF at big oil raising their prices through the roof which in turn has decimated sales of the high profit margin SUV and pickup trucks.
My car specifies 91 Octane if you want the full 280 HP. If I use 87, the car will retard the timing to prevent knock and I will lose HP. How much, I don't know.
MY BIG BEEF IS THE COST DIFFERENCE BETWEEN 87 AND 91.
There is no justification for 11 cents a litre more for 91. I doubt that it costs a half cent more for them to make 91 octane vs. 87.
In quebec, the differential between 87 and 91 is 6 cents.
In NY state, the differential was about 12 cents A GALLON
We are getting fucked as usual by big oil.
One last thing, if your car calls for 91 and you use 94, you will not get any better performance what so ever.
I also use premium in my German car and was always pissed having to pay 11 cents more per litre, but lately has anyone else noticed that premium is now only 6 cent more than regular ? The first time I saw that I thought it was a mistake but my last few fill ups have all bean 6 cents more !!! I guess we were really getting screwed before !!
I've alway's used mid-grade in my car. I went to Esso to fillup the other day and the guy told me there no longer supplying mid-grade. I had to use premium at $1.16 a litre. When I asked him why, he said it was because of the Gov't mandate that they mix in 10% ethanol into the gas and that the mid-grade couldn't ahndle it. So they've taken it off the market. Personally, I think it's bull s&^t ! Anybody else hear about this ?
BS
BS
Strongbeau said:My pumping is always high octane.
Good for you, just be careful you don't sprain your wrist.
Pretend this is a big grin smilie.
.
You can use a lower grad, but................
.....the lower grade gas will cause pinging and will be burned less efficiently in your engine. It is better to use the recommended gas for your car. You will get better mileage and better preformance. You engine will also work with less strain and last longer.
.....the lower grade gas will cause pinging and will be burned less efficiently in your engine. It is better to use the recommended gas for your car. You will get better mileage and better preformance. You engine will also work with less strain and last longer.
Hey man if you can afford to drive a car that only runs on high octane gas, then you should be able to afford that gas . Maybe you can turn your a/c off on these really hot days like the peeps I see driving around in their $50,000 suv's. Then you will save about 10 bucks in gas, lol. My car runs on any gas, even says so in the manual, its just awesome.
. Maybe you can turn your a/c off on these really hot days like the peeps I see driving around in their $50,000 suv's. Then you will save about 10 bucks in gas, lol. My car runs on any gas, even says so in the manual, its just awesome.Nothing scientific here, but back when I was racing horses all over the province, I found that my GMC Sierra got better mileage and had more power when towing a 2 horse trailer, when I used premium gas instead of regular.
Same two horses, weighing the same, same distance, exactly the same route each time, same speed, etc.
Same two horses, weighing the same, same distance, exactly the same route each time, same speed, etc.
Yours is a turbo engine, be safe, use the highest grade fuel you can afford. Boost + high compression significantly increases the likelyhood of detonation.
Is the fuel octane grade indicative of the amount of hydro-carbons? Does 91 octane contain 4.6% more hydro-carbons than 87 octane?
I do not think that you must run high octane fuel, it all depends on your driving style, the air temperature, and the density of the air, etc.... The best way to know is to actually track your air-to-fuel ratios after combustion using a tool called a wideband reader. You will have to weld another bung on the exhuast pipe, insert a special oxygen sensor and wire a gauge to your dash. This will allow you to see how much excess hydro carbons there are after combustion. For perfect combustion you need 14.7 parts of air to 1 part of fuel, however it is ideal to have ~13 parts of air to 1 part of fuel, because excess hydrocarbons slow down the combustion process and cool the engine. The tool costs about ~200 bucks and it will require some work to install it. It is not one of those RICE gauges as it is a very important tool and the information gathered from the tool will allow you to make educated decisions regarding the performance of your engine.
If you do not invest the time or money to find out about your air-to-fuel ratios you should play it safe and use high grade fuel.
Is the fuel octane grade indicative of the amount of hydro-carbons? Does 91 octane contain 4.6% more hydro-carbons than 87 octane?
I do not think that you must run high octane fuel, it all depends on your driving style, the air temperature, and the density of the air, etc.... The best way to know is to actually track your air-to-fuel ratios after combustion using a tool called a wideband reader. You will have to weld another bung on the exhuast pipe, insert a special oxygen sensor and wire a gauge to your dash. This will allow you to see how much excess hydro carbons there are after combustion. For perfect combustion you need 14.7 parts of air to 1 part of fuel, however it is ideal to have ~13 parts of air to 1 part of fuel, because excess hydrocarbons slow down the combustion process and cool the engine. The tool costs about ~200 bucks and it will require some work to install it. It is not one of those RICE gauges as it is a very important tool and the information gathered from the tool will allow you to make educated decisions regarding the performance of your engine.
If you do not invest the time or money to find out about your air-to-fuel ratios you should play it safe and use high grade fuel.
Octane is a measure of a fuel's resistance to knock (sometimes called detonation or pre-ignition). It is nothing more. It is not a measure of the chemical energy per unit volume of fuel or the number of hydrocarbons in it. The higher the the combustion chamber pressures are in your engine (the effective compression ratio) the higher the octane you need.bishop said:
I say effective compression ratios because turbo engines generally have low compression ratios (between 7 to 1 and 9 to 1) but are compressing a gas in the cylinder which may be at 1.25 to 2.0 times atmospheric pressure. They therefore have combustion chamber pressures at full throttle that may greatly exceed those of a high compression engine (at say 11 or 11.5 to 1). Higher compression engines have thermodynamic advantages over low compression engines and can generally have more power at the expense of being pricier and more difficult to build, more expensive to fuel and being prone to reduced longevity unless high quality materials are used in their construction.
If you have a high compression engine (either high compression ratio or turbo or supercharged) you should be using higher octane fuel. It will save you money and be better for the engine.
The requirement for higher octane fuel has nothing to do with air/fuel ratios. Most modern cars already have some sort of oxygen sensor in their emission control system which allows your car's computer to control the mixture. It will vary the mixture for the required situation generally trying to run a bit lean, keep unburned fuel to a minimum and have free oxygen in the exhaust for the catlytic converters. So monitoring the oxygen level with a second sensor will tell you nothing about whether the octane level is correct. You need to monitor detonation in the engine to determine if the octane is correct. Most modern cars come with a knock sensor to do just that. It will be used to adjust mainly the timing if the octane level is inadequate. If this is the case in a modern car you will not likely hear knock. You will just notice a lack of power and poorer fuel economy.
