93 octane fuel
 

I am not able to find 93 octane (or higher) fuel in Los Angeles, readily available....
I was just wondering what are you folks living in So Cal. using...
Do you think 91 fuel is just fine?

91 is just fine. If you track, buy some unleaded race gas at track.

Thanks. I do not track, so I will just stick to 91.

91 here in Colorado as well. No problems

So the "min 93 octane" written on the fuel cap of my 991 is probably just a recommendation to achieve the full engine potential...

not really...for that you need the 97+ they have at the track!

How long have you lived in LA? We used to have 92, while I was living on the east coast a few years back they switched to 91 (we had 93 there, and sunoco had 95).

91 is fine. Or you can drive to fontucky or rosamond and get 100 octane for $9/gallon.

You would want the 93 on hot summer days when you are pushing the car hard. For normal driving, 91 is going to be fine. In a modern car, you won't damage anything with a lower octane fuel in the tank as the DME unit will simply adjust the timing when the anti-knock sensors detect a ping, and you will simply lose a few HP off the top. Hot days tax the engine more than cool days, too.

I just recently relocated to LA, from Mass...
I also saw the 100 octane fuel for 9 bucks...that's the price I used to pay in Europe for normal gas...

The problem is in CA 91 is highest you can get anywhere except for race gas dealers.

Back before the present Research Octane plus Motor Octane (R+M) divided by 2 stickers on the pumps, the highest octane available at the pumps was the Chevron white pump Supreme or Union 76 Super. They were around 100+ research octane. Todays R+M divided by 2 stickers would have put them both at 96 octane.

I found a place not too far from me in Fullerton CA based on info from this site:

http://www.davebarton.com/Unleaded_Racing_Fuel_in_SoCal

There is a octane blending calculator out there in the interwebs too. I recall it being about 1 gal of 100 octane per 1/4 tank for a C2 or C2S. The C4's, turbos and GT3's have larger tanks so they might be closer to 1.25 gal per 1/4 tank.

If you find 104 or 110 octane, then the mix will obviously be different if you are shooting for 93. From what I can tell, most of these CA stations carry Sunoco GT100 (100octane) as it is approved for street legal cars and has no dyes in the fuel, unlike the race gas sold at the tracks which has dyes.

The "Butt Dyno" says it makes a difference, but it's probably only worth it if you are tracking the car or ripping to redline all day long. I did notice a difference with my 2003 E46 M3 when belnding, but not so much with the 991 C2S. May be a subtle difference I haven't picked up on yet.

Great info. Thank you!

We have 97octane available at most stations here in England.....but it's about $2/litre!

Yes. The engines are tested, certified for fuel consumption and emissions using 93 octane gasoline. (98 in Europe. The difference is how the octane numbers are calculated.)

The owners manual I think though cautions against going below 90.

91 is ok but not ideal but the engine will be ok. I've lived in CA now since 2004 with my Boxster and it has had nothing but 91 octane gasoline and is still doing just fine with I might add now over 285K miles on its engine.

Even my Turbo, which I've owned since 2009 and have put around 115K miles on since buying it used in 2009 runs ok with 91.

As others have advised if you are going to the track though dump in some high octane racing gasoline, unleaded of course. Up to you but I would not cut it too fine on the octane. That is to say I would not spend any time trying to blend 91 and 100 to arrived at precisely 93. I'd just dump in enough 100 with whatever amount of 91 was in the tank to get 93+. I'd probably err on the side of caution and end up with over 93 in the tank. An engine's octane requirements goes up with use so the octane in excess of 93 is not for naught.