89 octance gas
#21
10-19-2006 | 09:01 PM
2nd Gear
Joined: Aug 2005
Posts: 675
From: Florida PC
RE: 89 octance gas
points were made and taken. Lower octane fuel can cause your engine to ping. And I say can. Very rare cases of this with audi. Though there is a power and fuel mileage diffrence. The car uses more of the lower octane because it compinsating for the power loss I think it like a loss of 150hp jk like .987 hp. Run what the factory recomends though 87 is not going to kill your engine. The diffrences are very small
#22
10-19-2006 | 09:21 PM
2nd Gear
Joined: Oct 2006
Posts: 525
From: Minneapolis, MN
RE: 89 octance gas
If I go through a tank of gas a week, and pay the extra $.20/gallon for higher octane gas, that runs me about $166 per year. Now, I'm no rocket scientist, or combustion engineer, or financial consultant. I just park cars. But that isn't enough to purchase a new engine, even if extrapolated over 10 years. But hell, if you wanna feel like you got four free tanks of gas every year, burn what you want. I will be paying my $166 annual insurance premium, just to be safe. I just park cars. I don't want to risk f'ing something up that I can't afford to fix. If saving $166 a year matters that much to you, you probably can't afford to risk it either.
#25
10-19-2006 | 10:59 PM
3rd Gear
Joined: Feb 2006
Posts: 1,764
From: Ames, IA
RE: 89 octance gas
ORIGINAL: mandeepkang
OKAY, OKAY TOUGH GUYS...I SHOULDNT HAVE POSTED THIS IF YOU GUYS R GUNNA ACT LIKE A BUNCH OF BBBIIIAATTCHHSSS. HAHA I WILL STICK TO WUT THE DEALER/MANUAL SAYS 91 TO 95 OCTANE.
OKAY, OKAY TOUGH GUYS...I SHOULDNT HAVE POSTED THIS IF YOU GUYS R GUNNA ACT LIKE A BUNCH OF BBBIIIAATTCHHSSS. HAHA I WILL STICK TO WUT THE DEALER/MANUAL SAYS 91 TO 95 OCTANE.
#26
10-19-2006 | 11:17 PM
2nd Gear
Joined: Aug 2006
Posts: 619
From: NY
RE: 89 octance gas
ORIGINAL: Nvr2loud
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
You would think a 'combustion technician' would know more about timing retardation. I would also think that such a car guru would know more about the importance of proper maintenance. Yea, that whole section in the manual about changing the oil is just a suggestion, you don't have to do it if you don't really want to. That C- he pulled off to get his 'combustion technician' certificate is starting to show.
#27
10-20-2006 | 12:38 AM
Senior Member
Joined: May 2006
Posts: 491
From:
RE: 89 octance gas
ORIGINAL: Nvr2loud
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
Yes, there are several mechanics here. Me? I have degrees in mechanical engineering and physics and manage a gas/oil/electric heating appliance certification program for a living.
If you want to get technical, octane rating on fuel at the pump isn't related to the quantity of "octanes" in the liquid. It IS a measure of a fuel's pre-ignition or knock resistance. So theoretically you can have a fuel with no octane and an octane rating of 100.
Next, a lower octane fuel stands a better chance of igniting before the spark plug wants it to (pre-ignition). This pre-mature ignition occurs before the ideal moment that would give the crank a smooth kick and instead causes a brief counter force to the natural turn in the crank. Damage may occur because you're putting undesirable stress on your crank.
A lower octane fuel also stands a better chance of knocking/pinging. What happens here is the air/fuel mixture doesn't burn in a nice smooth fashion originating from the plug across the chamber but instead originates on multiple fronts independent of the plug. Erratic combustion like this can cause head gasket failure and other damage.
Oppositely, a high octane-rated fuel helps ensure it takes a hotter ignition source to ignite the fuel and not just a high temperature or pressure. This helps the ECU by giving it more control over the timing, thus better performance. If the car has to work harder to adjust it's timing when using lower octane fuel, you stand to lose HP and MPG.
Lastly, the thermal behavior of the cylinder is a function of the compression ratio. A higher ratio likes a higher octane. My stock '02 A4 has a compression ratio of 10:1 while, say for example, a 2002 civic type R has an 11:1. Feel free to advertise your career and push your 87 on a honda forum but don't come near me or Blue.
When you think about it, there's a reason professional racers use 100 octane (racers, not ricers...). Their cars get HOT and they will lose valuable performance if they pre-ignite during a race (race, not rice). In the end, each car is different. One may handle lower octane better than another. It's up to each person to find a nice groove for their car. As you can see, most intelligent Audi people that perform regular maintenance on their cars prefer the highest they can get.
Don't come on here announcing your job title like we should all be in AWE (free plug) and be all condescending. By the way, did I mention I have an MBA as well? Yea, get back in your little lab and I'll send some schmo down to slip your lunch under the door. Pull that crap again and I'll fire your *** (no pun intended... eh, yea it was... screw you).
swans here
#30
10-20-2006 | 08:53 AM
4th Gear
Joined: Oct 2004
Posts: 5,441
From: Chicago Burbs /// KOTH 06'
RE: 89 octance gas
ORIGINAL: wolfdog
Yes, there are several mechanics here. Me? I have degrees in mechanical engineering and physics and manage a gas/oil/electric heating appliance certification program for a living.
If you want to get technical, octane rating on fuel at the pump isn't related to the quantity of "octanes" in the liquid. It IS a measure of a fuel's pre-ignition or knock resistance. So theoretically you can have a fuel with no octane and an octane rating of 100.
Next, a lower octane fuel stands a better chance of igniting before the spark plug wants it to (pre-ignition). This pre-mature ignition occurs before the ideal moment that would give the crank a smooth kick and instead causes a brief counter force to the natural turn in the crank. Damage may occur because you're putting undesirable stress on your crank.
A lower octane fuel also stands a better chance of knocking/pinging. What happens here is the air/fuel mixture doesn't burn in a nice smooth fashion originating from the plug across the chamber but instead originates on multiple fronts independent of the plug. Erratic combustion like this can cause head gasket failure and other damage.
Oppositely, a high octane-rated fuel helps ensure it takes a hotter ignition source to ignite the fuel and not just a high temperature or pressure. This helps the ECU by giving it more control over the timing, thus better performance. If the car has to work harder to adjust it's timing when using lower octane fuel, you stand to lose HP and MPG.
Lastly, the thermal behavior of the cylinder is a function of the compression ratio. A higher ratio likes a higher octane. My stock '02 A4 has a compression ratio of 10:1 while, say for example, a 2002 civic type R has an 11:1. Feel free to advertise your career and push your 87 on a honda forum but don't come near me or Blue.
When you think about it, there's a reason professional racers use 100 octane (racers, not ricers...). Their cars get HOT and they will lose valuable performance if they pre-ignite during a race (race, not rice). In the end, each car is different. One may handle lower octane better than another. It's up to each person to find a nice groove for their car. As you can see, most intelligent Audi people that perform regular maintenance on their cars prefer the highest they can get.
Don't come on here announcing your job title like we should all be in AWE (free plug) and be all condescending. By the way, did I mention I have an MBA as well? Yea, get back in your little lab and I'll send some schmo down to slip your lunch under the door. Pull that crap again and I'll fire your *** (no pun intended... eh, yea it was... screw you).
ORIGINAL: Nvr2loud
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
Seriously! I've always run 87 octane in my car, I've never bothered with anything higher because the car dosen't knock on the 87. Higher octane gas isn't 'better' or 'cleaner' it just has a higher octane value. Anyone here a mechanic??? I'm a combustion technician, I know what I"m talking about. Loss of power hahahahaha LMFAO silly silly people.
Owner's manual says 89 octane recommended but minimum 87 okay. Unless it knocks with 87, I'll save my money.
Note: I've got 230,000 km on my A4 without a single engine problem ever. I'm the worst for maintenance, rarely change the oil, never changed spark plugs, rarely change the air filter.... the engine is more durable then any other engine I've ever had. Why baby the car, it's only a car!
Yes, there are several mechanics here. Me? I have degrees in mechanical engineering and physics and manage a gas/oil/electric heating appliance certification program for a living.
If you want to get technical, octane rating on fuel at the pump isn't related to the quantity of "octanes" in the liquid. It IS a measure of a fuel's pre-ignition or knock resistance. So theoretically you can have a fuel with no octane and an octane rating of 100.
Next, a lower octane fuel stands a better chance of igniting before the spark plug wants it to (pre-ignition). This pre-mature ignition occurs before the ideal moment that would give the crank a smooth kick and instead causes a brief counter force to the natural turn in the crank. Damage may occur because you're putting undesirable stress on your crank.
A lower octane fuel also stands a better chance of knocking/pinging. What happens here is the air/fuel mixture doesn't burn in a nice smooth fashion originating from the plug across the chamber but instead originates on multiple fronts independent of the plug. Erratic combustion like this can cause head gasket failure and other damage.
Oppositely, a high octane-rated fuel helps ensure it takes a hotter ignition source to ignite the fuel and not just a high temperature or pressure. This helps the ECU by giving it more control over the timing, thus better performance. If the car has to work harder to adjust it's timing when using lower octane fuel, you stand to lose HP and MPG.
Lastly, the thermal behavior of the cylinder is a function of the compression ratio. A higher ratio likes a higher octane. My stock '02 A4 has a compression ratio of 10:1 while, say for example, a 2002 civic type R has an 11:1. Feel free to advertise your career and push your 87 on a honda forum but don't come near me or Blue.
When you think about it, there's a reason professional racers use 100 octane (racers, not ricers...). Their cars get HOT and they will lose valuable performance if they pre-ignite during a race (race, not rice). In the end, each car is different. One may handle lower octane better than another. It's up to each person to find a nice groove for their car. As you can see, most intelligent Audi people that perform regular maintenance on their cars prefer the highest they can get.
Don't come on here announcing your job title like we should all be in AWE (free plug) and be all condescending. By the way, did I mention I have an MBA as well? Yea, get back in your little lab and I'll send some schmo down to slip your lunch under the door. Pull that crap again and I'll fire your *** (no pun intended... eh, yea it was... screw you).
its a wonderfull explanation.