What kinda gas do you use?

[auh]

I put in 93 octain most of the time but sometimes b/c of price I have to go with 89.

What do you all use? Any brand of gas you like imperticular?

[seaboltman]

Trust me, that $2 you save on putting in 89, has a possibility of causing more damage then saving $2 is worth

[Jmasters]

I thought 87 octane was just fine for 84's gas flap says 91ron and i thought that converted to 87 octane here in the states

[PCA 944]

Stick with 93, or with the inferior 91 us californian's are forced to endure. The 944 should be treated like a rich snoby teenager, if you dont treat it right it will rebel. Pay the extra few dollars, and rest assured that the future repair bill will be lower.

In my 86' 944 I noticed a large improvement in performance with 91 instead of 89.

[procon]

89

[ERAU944]

i use 87 all the way. i never get any pinging in either my car or my dads 27k mile '83. if i got pinging like i did in my miata, i'd use 89 like i do in that. use the lowest grade octane you can without pinging for maximum performance.

-Mike-

[CJFusco]

people still have the wrong impression of octane rating.

Octane rating has nothing to do with the "quality" of the gasoline. The terms "Regular," "Plus," and "Premium" are just a clever advertising ploy that the gas companies thought up in order to "up-sell."

This is the difference between 87 and 93 octane, according to a Stefan Wilkinson book: "The truth is that the chemical compounds that raise gasoline's octane rating are added simply to delay the onset of detonation. They produce no extra power. If your car never pings with 87-octane in the tank, 93-octane super will do nothing but snatch an extra two dimes per gallone out of your purse."

See this thread: Don't waste your money on high-octane gas - Stefan Wilkinson explains

[ERAU944]

as a side note - cars with higher compression - turbos, S2, S's and 88/89 944s will require higher octane to keep from detonating. as CJFusco said - the octane number is the anti-knock/ping index. the higher it is the 'less volatile' or prone to detonation the fuel is, i.e. it's harder to get to ignite. when you hear turbo guys talk about HP numbers on pump gas vs. really high octane gas, that's because they can turn the boost (compression) up with the really high octane stuff and get more out of their engines.

go easy on your car and your wallet, don't fall for the hype!

[auh]

I use 93 just because I see a huge difference in gas milage. When I first got the car I used 87 and was getting about 210 miles to a tank. Now I get 210 before I'm at a quarter of a tank with 93.

[bearone2]

over the years i tried years the hi test stuff, getting the best all around, no ping, easy start, good running from chevron sul but the litle bit of a mileage increase wasn't enuff to offset the +.20/gal over the 87.

i use 87, no ping, easy start, good running.

[livewirevoodoo]

Some interesting FAQs on gas octane:

http://www.faqs.org/faqs/autos/gasoline-faq/part1/
More than you'd ever wanna know about gasoline.

http://www.dealers.gmcanada.com/english/maintenance/goodwrench/understanding/gw_cardoc_faq.html#5
"The octane number or octane rating is a measure of the anti-knock properties of gasoline -- a higher number indicates a smaller likelihood of knocking. Using a higher-octane fuel than your Owner's Manual calls for is a waste of money. It doesn't produce more power, performance or fuel savings. Follow the Owner's Manual recommendations regarding fuel octane for your vehicle. The only time that higher octane fuels might be necessary is if your vehicle suffers audible engine knock at highway speeds."


http://www.repairfaq.org/filipg/AUTO/F_Gasoline6.html#GASOLINE_001
What do Fuel Octane ratings really indicate?


Pretty conclusive IMO.. Google "gas octane faq"... from chemists to dentists, everyone is pretty much in agreement that a higher octane only helps for knock.

I use 87 myself.. I pocket the difference between that and premium, and spend it on booze n hookers.

[Taz's Master]

If the engine uses a knock sensor and retards timing when it senses knock, then using higher octane can actually increase horsepower if it allows for more agressive timing and a leaner mixture.

[fast924S]

I run 93 since I did the rebuild, and I try to stick with mobil. Dont reallt know why just like it, also I have torn down my motor before and 93 seems to burn cleaner, not as much carbon in the head

[DannoXYZ]

"What kinda gas do you use?"

Custom mix of race-gas, toulene/xylene, and nitro-methane...

[bluebullet]

I use 93. The higher compression in my motor (10.6:1) doesnt like anything else. It seems to run slower (the first day I had it I filled it with 93, and a week later the gas dude put 10 dollars of 87 in with me not knowing, and the car just felt weird...slow on response) on the cheaper stuff. That and it had more of a tendancy to diesel when I shut the car off.

I would like to try some unleaded 100 sometime and see what it does...

[Techno Duck]

So what exactly would be the factory recommendation for an '87 944. I am not with my car until friday to check. I could never understand the RON method, octane rating stuff.

[Trevor]

Danno, running rocket fuel? My dad and I argue over this back and forth. He refuses to put premium in his new turbo volvo while I say it is necessary, the car will run cooler and and last longer. In an interesting side note on piston aircraft as you lean the mixture the exhaust gas temp. increases significantly. Does the difference in octane have the same effect on a car? I think the extra .10-.20 is worth the peace of mind. I'll be interested to hear more comments.

[ERAU944]

i was told that running avgas (100LL) in my car would cause problems due to lower specific gravity of that fuel leaning the mixture. i did notice that instead of the usual black carbon i was getting tan/grey in the exhaust. that's normal on aircraft too, so it didn't worry me. i was also told to change my oil soon after due to the combustion deposits in the oil.

Gah! avgas is leaded! Contgrats, you just destroyed your catalytic converter.

[rb101]

I'm scared to use anything under 92 on the S. Everything else gets 87