Fuel these days... - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Cloudsurfer · 10-03-2009, 08:14 AM

If you want "gasoline," try race fuels or avgas (unfortunately, avgas is highly leaded). The crap that they call "gas" that goes in your street car is highly diluted and filled with who knows what. Formulations differ from company to company, state to state, and season to season.

mptoledo · 10-03-2009, 07:36 PM

I try to use the following site(click on retailer) as a general idea what gas isn't crap, but in my small area I am lucky to find a Shell station and Chevron is out of the question.

http://www.toptiergas.com/index.html

edevlin · 10-03-2009, 10:09 PM

" but in my small area I am lucky to find a Shell station and Chevron is out of the question"

Me too, we only have a Chevron, but it is a small, old facility with low volume. We do have a new Sheetz which I am thinking of switching to. They are supposed to have high-quality fuel storage and delivery systems, but I am not sure about their fuel, as they are not listed as toptier. Anyone have experience with their fuel?

Ed

pk2 · 10-04-2009, 09:50 AM

I run a 9:1 mix of race fuel just because I kinda have to, can't afford any extra heat. We don't even have 93 cot here. I like to use chevron. Techronn is pretty legit harmless detergent. 20 odd years a ago I got a bum tank of gas from a no-name station. All it did was smell so stong and bad I discovered a leaking fuel line (good idea for leaky fuel finder...some sort of skunk additive).

Turn the question around, anybody had a big problem with less than fresh "High quality" fuel?

PK

ekam · 10-05-2009, 04:55 AM

Our Sunoco 94 oct also contains 10% ethanol. Lots of local Pcar guys switched to Shell 91 oct and they notice better gas mileage right off.

blue2000s · 10-05-2009, 06:28 AM

Check this out:

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

You thought oil was a complicated mixture!

pk2 · 10-05-2009, 07:46 AM

Quote:

Originally Posted by blue2000s

Check this out:

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

You thought oil was a complicated mixture!

--------------------------------------------------------------------------------
I noticed "toluene" on the list as an anti knock additive. Never had a knock but that's just because the timing will be automatically retarded, but that will effect performance. I use Toluene in a pinch to up the octane, It has debatable burn characteristics but it is cooler.

That's strange the higher oct. gives worse mileage. Here in CA we get to set the standards for some 12 other states(sorry) (instead of looser fed standards). I thought we oxygenated with alcohol everything, 87-91 oct. No escape. It use to be just a summertime thing but I think it's year around now.

Is performance wonder how much performance is effected with 91 oct.

Regards, PK

mptoledo · 10-05-2009, 06:32 AM

I noticed a drop in MPG when I was using "Clark" station's fuel ( I am guessing their ethanol mix is higher). Nothing bad with performance though, just a drop in mpg. I switched back to shell and the mpg is back up 3 to 5 mpg. Bad part is, my Shell station is in a very small town and is always .10 to .15 higher.

Quote:

Originally Posted by pk2

I run a 9:1 mix of race fuel just because I kinda have to, can't afford any extra heat. We don't even have 93 cot here. I like to use chevron. Techronn is pretty legit harmless detergent. 20 odd years a ago I got a bum tank of gas from a no-name station. All it did was smell so stong and bad I discovered a leaking fuel line (good idea for leaky fuel finder...some sort of skunk additive).

Turn the question around, anybody had a big problem with less than fresh "High quality" fuel?

PK

tnoice · 10-05-2009, 07:33 PM

Quote:

Originally Posted by mptoledo

I try to use the following site(click on retailer) as a general idea what gas isn't crap, but in my small area I am lucky to find a Shell station and Chevron is out of the question.

http://www.toptiergas.com/index.html

wow, we officially do not have a single one of those gas stations here in champaign/urbana. I just do not know what to say, our gas sucks... But being in the mid west we have good dirt and corn. Maybe thats why we have so much ethanol!

mptoledo · 10-08-2009, 01:03 PM

Quote:

Originally Posted by tnoice

wow, we officially do not have a single one of those gas stations here in champaign/urbana. I just do not know what to say, our gas sucks... But being in the mid west we have good dirt and corn. Maybe thats why we have so much ethanol!

Champaign urban? I live in Urban in Champaign county. Who would have thunk it.

It might take a little leg work to find a station w/out Ethanol. I am still looking and the station attendants aren't too helpful either.

d18mike · 10-06-2009, 10:08 AM

Here's the official/unofficial word from a Porsche engineer on non-premium fuels (USA Today, 2003)

... All Porsche engines are designed for premium, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using standard octane gas, even in the highest-performance, regular-production Porsches.

blue2000s · 10-06-2009, 10:33 AM

Quote:

Originally Posted by d18mike

Here's the official/unofficial word from a Porsche engineer on non-premium fuels (USA Today, 2003)

... All Porsche engines are designed for premium, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using standard octane gas, even in the highest-performance, regular-production Porsches.

Yup, that's typical of all manufacturers. Most cars today are equipped with knock sensors that can retard spark timing to protect the engine from damage if the gasoline isn't of expected octane rating. There's a power penalty and some argue that the lower octane fuels don't clean the engine as well because of the formulation.

mptoledo · 10-06-2009, 12:42 PM

Has anybody tried regular or even midgrade? I will stick to high grade until I can do some more research on the subject.

Also: Anybody have any input on mobil gas? I found a UDF (united dairy farmer) gas station and it's tanks are labled MOBIL.