safe to use lower octane levels? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

mapleglen porsche · 06-01-2008, 02:41 PM

with the price of gas, how safe is the lower octane gasoline with 2004 boxster. I've used 87 on occasion when 93 octane wasn't available and I did not notice any dramatic problems. Anyone have any feed back?

06-01-2008, 02:46 PM

Not Safe.

The right gas will cost about $100 more per year over the "cheap" stuff.

Quickurt · 06-01-2008, 02:50 PM

In an emeergency, okay.
We've been through the rest of it already. You are more than likely not saving any money as you will save less than 3% on money and lose about 10% on fuel consumption.
I haven't tried it in my boxster, but I did a good back to back in my Mazda Turbo and lost over 12% in gas mileage while gaining less than 3% in dollar savings.

Quickurt · 06-01-2008, 02:53 PM

I guess an emeergency is when there's nothing but regular or mid-grade available.

An eemergency is when you click the post button before reading over what you typed.

An emergency is when I actually sit at a keyboard!!

pbanders · 06-01-2008, 03:16 PM

We have 87, 89, and 91 RON here in AZ. I ran 89 for about 6 months in my M3, and while I didn't really notice any performance difference (as judged by the unreliable "seat of your pants" dyno), the idle became rougher over time. I switched back to 91 and within a few tanks the idle was perfect again. My Box has only seen 91, and my 914 won't run on (knocks) if I use anything other than 91, and actually works best on 93 (I can slightly advance the timing and get a bit more power).

KevinH1990 · 06-01-2008, 06:26 PM

I've seen some evidence that it will run well on regular, but I am cautious about switching.

A fellow I worked with until a couple of weeks ago uses regular in his 04 non-S. He e-mailed me the other day and said he was getting 31 mpg with no noticeable decline in performance. He did tell me he was trying to coast up to traffic signals and not drive as fast as he would like.

I'm cautious because I don't know anyone who has used regular for a long period of time. I just completed the process of sorting out some problems with my fuel system. My car is running fine now, so I'm staying with 93 octane fuel. I don't want to disturb my cars equilibrium, and I won't switch until I see some really hard data and not just anecdotal evidence. The savings is about 20 cents a gallon in my area, so that is less than a penny a mile when driving on the highway.