87 sc?
#32
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i wouldnt worry about going to Cosco to get gas. Gas for a particular region usually originates from the same refinery. ie arco regular is the same regular at 76 or Shell. The only real difference is the additives each retailer adds; the most effective detergent is Chevron's techroline.
Rust in the injectors typically comes from moisture in the fuel. The most common way people get water in the fuel is by keeping the tank fueled low and keeping their car outside which causes condensation in the tank. Occasional tankfuls of Chevron's best and keeping the tank ful as much as possible will keep the injects up to snuff.
Rust in the injectors typically comes from moisture in the fuel. The most common way people get water in the fuel is by keeping the tank fueled low and keeping their car outside which causes condensation in the tank. Occasional tankfuls of Chevron's best and keeping the tank ful as much as possible will keep the injects up to snuff.
#34
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If ya'll really want to learn how octane works you should check out this link:
http://science.howstuffworks.com/gasoline3.htm
Basically, octane is the ratio of octane to heptane in the gasoline. When a gasoline engine compresses it is important that the gasoline not detonate on its own, and that it combust when the spark plug fires. The lower the ratio of octane (ex: 87/13) the lower the ammount of compression it can withstand. Since the SC's engine is designed pretty aggressively witha relatively high compression ratio, it requires higher octane ratings to prevent premature detonation. Otherwise, according to what I read, 87 octane will not have a direct effect on carbon deposits or anything like that. It could just really screw up the motor if it pings too early. The o2 sensor should compensate for changes is the air/fuel ratio.
http://science.howstuffworks.com/gasoline3.htm
Basically, octane is the ratio of octane to heptane in the gasoline. When a gasoline engine compresses it is important that the gasoline not detonate on its own, and that it combust when the spark plug fires. The lower the ratio of octane (ex: 87/13) the lower the ammount of compression it can withstand. Since the SC's engine is designed pretty aggressively witha relatively high compression ratio, it requires higher octane ratings to prevent premature detonation. Otherwise, according to what I read, 87 octane will not have a direct effect on carbon deposits or anything like that. It could just really screw up the motor if it pings too early. The o2 sensor should compensate for changes is the air/fuel ratio.
#35
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Don't forget the whole MTBE vs. ethanol thing. I think that's why Valero/Arco/Costco seem to be cheaper in Cali right now vs. Shell/etc. cuz by Cali law, all stations are required to convert to using ethanol by 2004 which is more expensive than MTBE. And Valero and Arco are slower to convert, so get the cheaper gas from them while they last.
#37
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The MTBE-ban is a farse! The issue was way overplayed back in 1999. Davis suspended the MTBE phase out in March 2002 for various reasons:
- Ethanol reformulation would increase the gas shortage in CA due to low supply levels in the region.
- Ethanol reformulation would further increase gas prices due to the high distribution costs from the Midwest and increased dependency on imported gasoline.
- This would result in extended seasonal gas shortages causing upwards of $0.50/gallon price spikes. Does anyone want +$3/gallon prices to be the normal rate in CA?
- Ethanol reformulation in CA would create an over-concentrated market with ADM, the largest ethanol producer in the nation. This would give ADM more leverage in setting ethanol prices!
- MTBE contamination levels were overestimated in 1996 and MTBE predictions were inaccurate.
- MTBE contamination was determined to be a fault of enforcement oversight on storage tank maintenance.
- MTBE contamination was due to gasoline storage tank corrosion unrelated to the MTBE additive alone.
- MTBE was later determined by a multitude of health organizations not to be carcinogenic, and furthermore not to pose any health risks or toxicity to humans at all! You can drink the stuff if you wanted to!
- MTBE contamination levels are relatively low on the list of ground water pollutants in CA, outranked by two dozen other contaminants that ARE toxic to humans.
- MTBE contamination has been contained and controlled in the last four years since the study's inital findings.
- Ethanol reformulation would increase the gas shortage in CA due to low supply levels in the region.
- Ethanol reformulation would further increase gas prices due to the high distribution costs from the Midwest and increased dependency on imported gasoline.
- This would result in extended seasonal gas shortages causing upwards of $0.50/gallon price spikes. Does anyone want +$3/gallon prices to be the normal rate in CA?
- Ethanol reformulation in CA would create an over-concentrated market with ADM, the largest ethanol producer in the nation. This would give ADM more leverage in setting ethanol prices!
- MTBE contamination levels were overestimated in 1996 and MTBE predictions were inaccurate.
- MTBE contamination was determined to be a fault of enforcement oversight on storage tank maintenance.
- MTBE contamination was due to gasoline storage tank corrosion unrelated to the MTBE additive alone.
- MTBE was later determined by a multitude of health organizations not to be carcinogenic, and furthermore not to pose any health risks or toxicity to humans at all! You can drink the stuff if you wanted to!
- MTBE contamination levels are relatively low on the list of ground water pollutants in CA, outranked by two dozen other contaminants that ARE toxic to humans.
- MTBE contamination has been contained and controlled in the last four years since the study's inital findings.
Last edited by lex400sc; 05-10-03 at 06:17 PM.
#39
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Originally posted by SC_Speed
If ya'll really want to learn how octane works you should check out this link:
http://science.howstuffworks.com/gasoline3.htm
Basically, octane is the ratio of octane to heptane in the gasoline. When a gasoline engine compresses it is important that the gasoline not detonate on its own, and that it combust when the spark plug fires. The lower the ratio of octane (ex: 87/13) the lower the ammount of compression it can withstand. Since the SC's engine is designed pretty aggressively witha relatively high compression ratio, it requires higher octane ratings to prevent premature detonation. Otherwise, according to what I read, 87 octane will not have a direct effect on carbon deposits or anything like that. It could just really screw up the motor if it pings too early. The o2 sensor should compensate for changes is the air/fuel ratio.
If ya'll really want to learn how octane works you should check out this link:
http://science.howstuffworks.com/gasoline3.htm
Basically, octane is the ratio of octane to heptane in the gasoline. When a gasoline engine compresses it is important that the gasoline not detonate on its own, and that it combust when the spark plug fires. The lower the ratio of octane (ex: 87/13) the lower the ammount of compression it can withstand. Since the SC's engine is designed pretty aggressively witha relatively high compression ratio, it requires higher octane ratings to prevent premature detonation. Otherwise, according to what I read, 87 octane will not have a direct effect on carbon deposits or anything like that. It could just really screw up the motor if it pings too early. The o2 sensor should compensate for changes is the air/fuel ratio.
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Note, in addiotion to the O2 sensor readings, the ECU can detect misfires and detonation and will retard the timing to correct it. This is why you *can* run 87 octane if you really want to and the ECU will compensate. I just don't understand why anyone would want to. The car will run better and be more efficient if it has the higher octane fuel to work with.
#40
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One would want to run regular fuel because the ECU doesnt start retarding the timing until engine speeds exceed 3000RPM. So, between idle and 3000RPM, performance is the same if not better. Since I use the SC for everyday use, this is the range I typically run.
One thing everyone needs to consider is that cool temperatures, high humidity, high altitude, and lower mileage reduce the demand for octane. So owners near the coast (where I'm at, and its been cold and rainy lately) need the Premo stuff less. Those in the Midwest & South will see more benefits from Premium.
One thing everyone needs to consider is that cool temperatures, high humidity, high altitude, and lower mileage reduce the demand for octane. So owners near the coast (where I'm at, and its been cold and rainy lately) need the Premo stuff less. Those in the Midwest & South will see more benefits from Premium.
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