A question about GAS

[efedor]

I am a proud owner of a 2004 Boxster(speed yellow), I have always used regular unleaded. I remember putting super unleaded maybe twice in it's life time. I use regular unleaded because of the price but also because the car ran smooth and responsive, so my question is...Is there really a difference between regular and super? Will I start having problems with the car? It has 30k miles and from what I read It's in a delicate stage of it's life. Any opinions are welcome, Thanks

[White987S]

Is there a difference? Yes

Should you use 93 Octane? Yes.

For the average driver (15,000 miles per year) with average MPG's (22) the proper fuel costs an additional $140 per year. trim your budget elsewhere.

[rsfeller]

Yea people with sports cars and boats should be overly concerned with gas cost from low to high...other wise you got the wrong toy.

http://en.wikipedia.org/wiki/Octane_rating

Running lower octane will not hurt anything since most modern cars can adjust the timing to compensate for any "ping" but at the same time you may not always be hearing it. You can notice a slight drop in performance by using low grade but under no means does putting higher octane is a car that requires low octane improve performance, that is a myth.

I guess the thing everyone is going to tell you is quit being cheap and taking the small chance of premature wear on your engine just to save $50-100 a year.

I found my wife has been putting low octane in my Saab V6 wagon which also wants high octane. I've noticed no difference in preformance, mileage or sound due to it...but I really don't want to take that chance in my Porsche with it's scary little engine.

[Tool Pants]

In California it is 87, 89, 91. I have a 1997 that I bought in 1999, as my only car and daily driver. I have used 87 for 9 years. A few times I have tried a tank of 91 and noticed no difference. There is supposed to be a slight decrease in power, something like a few hp, but it must be so small that I can't notice it. I have 67,000 miles and have no engine problems. I have never had any pinging - there are 2 knock sensors in case you did not know.

[tholyoak]

Keep in mind that the knock control can only pull out so much timing, it is there as a safeguard. By running octane below the requirement you are already pulling out timing under normal conditions. Couple that with otjer conditions such as high temps, and carbon buildup due to in town driving, that can promote detonation and you are gambling with your engine, especially if you drive the car like it was made to be driven. The car has an 11:1 compression ratio, putting in regular gas is just silly.

I really don't understand people who buy a car like a Porsche, presumably because they enjoy the performance driving experience (this excludes those who are just buying the car for a perceived image which is more popular these days as Porsche has shifted to being more of a luxury car company than a sports car company) and then cheap out on things like the recommended gas. Or buy cheap tires, shocks etc. Parts that have a direct influence on the driving experience of the car. Just my $0.02, take it for what it is worth.

-Todd

Edited May 9, 2008 by tholyoak

[White987S]

Keep in mind that the knock control can only pull out so much timing, it is there as a safeguard. By running octane below the requirement you are already pulling out timing under normal conditions. Couple that with otjer conditions such as high temps, and carbon buildup due to in town driving, that can promote detonation and you are gambling with your engine, especially if you drive the car like it was made to be driven. The car has an 11:1 compression ratio, putting in regular gas is just silly.

I really don't understand people who buy a car like a Porsche, presumably because they enjoy the performance driving experience (this excludes those who are just buying the car for a perceived image which is more popular these days as Porsche has shifted to being more of a luxury car company than a sports car company) and then cheap out on things like the recommended gas. Or buy cheap tires, shocks etc. Parts that have a direct influence on the driving experience of the car. Just my $0.02, take it for what it is worth.

-Todd

+1 here.

[Thanassis]

I am converting mine to propane! :)

[perryinva]

Personally, I think it is mor eimprotant to use quality Tier 1 gas than a higher octane, though I use 89 or better, depending on the driving. Both my Dodge truck, VW Passat, and Suzuki Sidekick throw fits, (ping, poor mielage, etc) if I use 87. I try to stick to Shell, Chevron, etc. In most places here, Premium is 93 and oxygenated and 10% ethanol, so I'll often fill up with 93 and alternate some 89 in there. on the interstate for a long trip, it doesn't seem to make any difference between 89 & 93, but for around town I do get better mielage with 93.

[rsfeller]

Personally, I think it is mor eimprotant to use quality Tier 1 gas than a higher octane, though I use 89 or better, depending on the driving. Both my Dodge truck, VW Passat, and Suzuki Sidekick throw fits, (ping, poor mielage, etc) if I use 87. I try to stick to Shell, Chevron, etc. In most places here, Premium is 93 and oxygenated and 10% ethanol, so I'll often fill up with 93 and alternate some 89 in there. on the interstate for a long trip, it doesn't seem to make any difference between 89 & 93, but for around town I do get better mielage with 93.

You make a good point and I should clarify my earlier post. High octane will not improve gas mileage for a car that is designed to run on 87 but if you care is designed to run on 93 then running 93 in it will give you better preformance and mileage then 87, it's a fact I've read 101 times.

Not sure I agree on the seller of gas since most run through a handful of the same processing plants in the US anyways, but others claim they notice. One thing I do know is that a majority of the gas companies buy from difference sources based on the economy of the supply and demand and who has the gas when they need it at good prices.

A couple good sources:

http://www.wanderings.net/notebook/Main/Is...worth-the-money

http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut12.shtm

I think everyone here will tell the poster that there is no GOOD reason to run low octane in a Porsche when it is recommended for 93, again to save $50-100 a year. It's more a mental thing at the pump having to buy $4.20 a gallon premium.

[jmatta]

Oh, OK, you're talking about fuel...when I saw GAS, I immediately assumed "Gear Acquisition Syndrome" (which many of us catch from time to time).

Edited May 9, 2008 by jmatta

[perryinva]

Personally, I think it is mor eimprotant to use quality Tier 1 gas than a higher octane, though I use 89 or better, depending on the driving. Both my Dodge truck, VW Passat, and Suzuki Sidekick throw fits, (ping, poor mielage, etc) if I use 87. I try to stick to Shell, Chevron, etc. In most places here, Premium is 93 and oxygenated and 10% ethanol, so I'll often fill up with 93 and alternate some 89 in there. on the interstate for a long trip, it doesn't seem to make any difference between 89 & 93, but for around town I do get better mielage with 93.

You make a good point and I should clarify my earlier post. High octane will not improve gas mileage for a car that is designed to run on 87 but if you care is designed to run on 93 then running 93 in it will give you better preformance and mileage then 87, it's a fact I've read 101 times.

Not sure I agree on the seller of gas since most run through a handful of the same processing plants in the US anyways, but others claim they notice. One thing I do know is that a majority of the gas companies buy from difference sources based on the economy of the supply and demand and who has the gas when they need it at good prices.

A couple good sources:

http://www.wanderings.net/notebook/Main/Is...worth-the-money

http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut12.shtm

I think everyone here will tell the poster that there is no GOOD reason to run low octane in a Porsche when it is recommended for 93, again to save $50-100 a year. It's more a mental thing at the pump having to buy $4.20 a gallon premium.

WHile the bulk base gasoline in the pipeline is usually the same, it is the additive packages that are added to the tanker trunks at fill up that make the difference..plus the Tier 1 suppossedly has higher filtration requirements. Since 2002 & later (996, not sure of 986/987) has no fuel filter, I'm not taking any chances!!!

[rsfeller]

Personally, I think it is mor eimprotant to use quality Tier 1 gas than a higher octane, though I use 89 or better, depending on the driving. Both my Dodge truck, VW Passat, and Suzuki Sidekick throw fits, (ping, poor mielage, etc) if I use 87. I try to stick to Shell, Chevron, etc. In most places here, Premium is 93 and oxygenated and 10% ethanol, so I'll often fill up with 93 and alternate some 89 in there. on the interstate for a long trip, it doesn't seem to make any difference between 89 & 93, but for around town I do get better mielage with 93.

You make a good point and I should clarify my earlier post. High octane will not improve gas mileage for a car that is designed to run on 87 but if you care is designed to run on 93 then running 93 in it will give you better preformance and mileage then 87, it's a fact I've read 101 times.

Not sure I agree on the seller of gas since most run through a handful of the same processing plants in the US anyways, but others claim they notice. One thing I do know is that a majority of the gas companies buy from difference sources based on the economy of the supply and demand and who has the gas when they need it at good prices.

A couple good sources:

http://www.wanderings.net/notebook/Main/Is...worth-the-money

http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut12.shtm

I think everyone here will tell the poster that there is no GOOD reason to run low octane in a Porsche when it is recommended for 93, again to save $50-100 a year. It's more a mental thing at the pump having to buy $4.20 a gallon premium.

WHile the bulk base gasoline in the pipeline is usually the same, it is the additive packages that are added to the tanker trunks at fill up that make the difference..plus the Tier 1 suppossedly has higher filtration requirements. Since 2002 & later (996, not sure of 986/987) has no fuel filter, I'm not taking any chances!!!

986 do, seriously in this day and age they have a reason not to have a filter? What would be the disadvantage?

[tholyoak]

The filter was not eliminated, there is simply no external replaceable filter like the earlier cars. There is still a filter, it is part of the fuel pump/level sensor in the tank and is a lifetime unit.

-Todd

[rsfeller]

The filter was not eliminated, there is simply no external replaceable filter like the earlier cars. There is still a filter, it is part of the fuel pump/level sensor in the tank and is a lifetime unit.

-Todd

I figured as much, it sounded like a squirrelly comment!

[perryinva]

I figured as much, it sounded like a squirrelly comment!

Not a squirrelly comment at all...what do you think it costs to replace the fuel pump unit JUST to replace the filter! Like ai said, I'll use better gas if it extends the life of the pump or car...

[RFM]

The filter in the pump unit should be replaceable separately.