View Poll Results: What gas do you purchase for your car?
Premium Only - I need all the ponies!
215
74.65%
Midgrade Only - Not primo but better than regular
24
8.33%
Regular - It's all the same to me
32
11.11%
Depends - Sometimes I feel like a premium, sometimes I don't
17
5.90%
Voters: 288. You may not vote on this poll
Merged 3GS Fuel Threads - Is it OK to use REGULAR gas Instead of PREMIUM?
#16
Lexus Connoisseur
Originally Posted by 1SICKLEX
3. You will get worse gas milege
#18
Originally Posted by DaveJ
I'm waiting on delivery of my GS300. Does the manual recommend 91 or 93 octane?
#20
Lexus Fanatic
iTrader: (20)
Originally Posted by DaveJ
I'm waiting on delivery of my GS300. Does the manual recommend 91 or 93 octane?
#21
Lexus Connoisseur
Originally Posted by bitkahuna
It has to say 91 and up (instead of 93) because you can't get 93 in CA I believe.
#22
gasoline
I guess, this will help you to understand why you need a higher octane gasoline for your Lexus.
http://www.howstuffworks.com/question90.htm
If you've read How Car Engines Work, you know that almost all cars use four-stroke gasoline engines. One of the strokes is the compression stroke, where the engine compresses a cylinder-full of air and gas into a much smaller volume before igniting it with a spark plug. The amount of compression is called the compression ratio of the engine. A typical engine might have a compression ratio of 8-to-1. (See How Car Engines Work for details.)
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.
It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
During WWI, it was discovered that you can add a chemical called tetraethyl lead to gasoline and significantly improve its octane rating. Cheaper grades of gasoline could be made usable by adding this chemical. This led to the widespread use of "ethyl" or "leaded" gasoline. Unfortunately, the side effects of adding lead to gasoline are:
• Lead clogs a catalytic converter and renders it inoperable within minutes.
• The Earth became covered in a thin layer of lead, and lead is toxic to many living things (including humans).
When lead was banned, gasoline got more expensive because refineries could not boost the octane ratings of cheaper grades any more. Airplanes are still allowed to use leaded gasoline, and octane ratings of 115 are commonly used in super-high-performance piston airplane engines (jet engines burn kerosene, by the way).
http://www.howstuffworks.com/question90.htm
If you've read How Car Engines Work, you know that almost all cars use four-stroke gasoline engines. One of the strokes is the compression stroke, where the engine compresses a cylinder-full of air and gas into a much smaller volume before igniting it with a spark plug. The amount of compression is called the compression ratio of the engine. A typical engine might have a compression ratio of 8-to-1. (See How Car Engines Work for details.)
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.
It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
During WWI, it was discovered that you can add a chemical called tetraethyl lead to gasoline and significantly improve its octane rating. Cheaper grades of gasoline could be made usable by adding this chemical. This led to the widespread use of "ethyl" or "leaded" gasoline. Unfortunately, the side effects of adding lead to gasoline are:
• Lead clogs a catalytic converter and renders it inoperable within minutes.
• The Earth became covered in a thin layer of lead, and lead is toxic to many living things (including humans).
When lead was banned, gasoline got more expensive because refineries could not boost the octane ratings of cheaper grades any more. Airplanes are still allowed to use leaded gasoline, and octane ratings of 115 are commonly used in super-high-performance piston airplane engines (jet engines burn kerosene, by the way).
#23
exclusive matchup
iTrader: (4)
Originally Posted by bitkahuna
It has to say 91 and up (instead of 93) because you can't get 93 in CA I believe.
#24
89 Octane vs. 91octane
When gas prices first started to rise, I tryed 89 octane in my 1993 GS. And i guess it did o.k for a while but i had just got off of the dan ryan express way and while i was bagging into my drive way i pulled it out to straighten up, and all of a sudden it cut off, and then it started right back up.
My advice is to u is to pay a little extra because in the long run you'll save big bucks.
My advice is to u is to pay a little extra because in the long run you'll save big bucks.
#25
Driver School Candidate
Join Date: Mar 2005
Location: UK
Posts: 30
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Gas Cost comparison
Reading this thread with interest, however, would you you guys consider cost as a major influencing factor in this decision if you were paying UK gas pump prices.....
Currently 1 Litre = £0.91 or 1 Litre = US$1.72
That works out at US$6.52 a gallon!
Yes that's what we are paying for gas at the pump here in the UK/England.......
Anyone want to fill up here?
Currently 1 Litre = £0.91 or 1 Litre = US$1.72
That works out at US$6.52 a gallon!
Yes that's what we are paying for gas at the pump here in the UK/England.......
Anyone want to fill up here?
#26
exclusive matchup
iTrader: (4)
Originally Posted by nortrack
Reading this thread with interest, however, would you you guys consider cost as a major influencing factor in this decision if you were paying UK gas pump prices.....
Currently 1 Litre = £0.91 or 1 Litre = US$1.72
That works out at US$6.52 a gallon!
Yes that's what we are paying for gas at the pump here in the UK/England.......
Anyone want to fill up here?
Currently 1 Litre = £0.91 or 1 Litre = US$1.72
That works out at US$6.52 a gallon!
Yes that's what we are paying for gas at the pump here in the UK/England.......
Anyone want to fill up here?
#28
Lexus Fanatic
iTrader: (20)
Originally Posted by nortrack
That works out at US$6.52 a gallon!
Do you guys know the U.K. has a 17.5% sales tax!?! It's already 'built in' to prices (you never see it at cash registers).
#29
Driver School Candidate
Join Date: Jun 2005
Location: ca
Posts: 26
Likes: 0
Received 0 Likes
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0 Posts
91 versus 87 grade octane fuel...
I recently purchased a 06 gs300 rwd a few weeks ago. Great Car!! It is recommended to use premium fuel on this automobile ( which I do). But, I keep hearing that 87 grade fuel is just as good and I'm wasting my money on the 91. Need your opinions.
Thanks.
Thanks.
#30
exclusive matchup
iTrader: (4)
there is a difference. our cars need 91+ fuel. with 87 it's ok, but the computer will retard its timing, and maybe you will get some pinging as well
just get 91. if you can afford the car you can afford the gas. overall using 91 you will spend like 200 bucks more a yr?
just get 91. if you can afford the car you can afford the gas. overall using 91 you will spend like 200 bucks more a yr?