Ahhh! My bad, meant ethanol....Hanging out at the drags too much!

... and sniffing too much methane?

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The 91octane pump (high test) says on it "ethanol free", the 87 octane pump (regular) says it contains 10 or 15% ethanol, I'm not sure which as I don't use it, maybe it's the law in Canada that they have to post the info. I used to run the refuelling section at Canadian Forces Base Greenwood in Nova Scotia and have had a few courses re. fuel, not just gasoline. I agree you only need to run the octane required for your engine not to knock/ping, but I have been running the 91 since the ethanol thing and like I said in a previous post, all those old mechanics that actually tear engines apart are running the 91. I know if I use a corner store gas bar of no name gas it isn't the same as Shell Gold, so that is what I use in all my vehicles.

Ian Stott
Moncton
Canada

I voted for 91 but I am running an 83sc 6 and from what I have read they bumped up the HP to 204 with all the smog/exhaust stuff! I have since removed all that and added headers. The specs on the later 80 to 83 sc's said to use 91!

You can buy a fuel tester on line, but I bought mine from the local Briggs and Stratton parts shop for $8. I test the fuel now and then when I buy gas for the lawn mower. The pump sticker says "contains up to 10% ethanol" but I haven't found any alcohol content here in OK for a couple of years and lately the stickers have disappeared at many stations. A few of the Fina -- now Alon -- stations here have a pump for 100% regular and another for 10% ethanol regular.

And I just bought 3 testers for Christmas gifts for fellow enthusiasts. And you can make one with a test tube from your kid's chemistry set.

Anyway, my 914 and '86 911 run fine on regular. And I like MMO a couple of times a year. It smells better than the other stuff, but its all "petroleum distillates" which I think usually means fuel oil, jet fuel, diesel, kerosene, etc.

Premium........it's a freaking Porsche.....Come on people

BTW, I run Marine stabilizer in every tank too......Ethanol is not our friend

Just because it's a Porsche, doesn't justify running expensive gas. If it doesn't ping on 87, run 87. the quality of gas does not improve as the octane increases, unless there's an increase in ethanol content as the octane goes down.

Plus, 914's have vw engines... No need to spend extra for wasted octane...

2.0 D-jet, 87 octane

I've tried everything from regular to super unleaded. I never noticed a difference. Just use regular now

I drive a conversion in a conversion that's wrapped up like a Taco Bell double decker turbo death burrito...

So premium is required. Know your overal pressures your dealing with. High comp will require it. Most stock type 4's properly tuned could run happy on regular forever.i imagine when you consider the compression ratio and quality of gas at the time of manufacture. But as I've made an ass of myself before.. I could be totally off.

What if you're running an MSD system on a original FI '73 2.0lt? I just had mine rebuilt to a 2056 and will be crancking it up soon after 20 yrs of rest. What grade should I start it at and for how long?
New rings, cylinders, redone heads, MDS coil, wires, plugs, Plantronix .......kitchen sink wouldnt fit.

Always run the lowest grade gas that does not cause your engine to ping.

My 2056 needed 93oct gas when it was at 9.2:1 compression. Its new form will be 8.6:1 compression and I will need to determine what grade gas to use when its running. If it does not ping on 87, thats what I will be using.

Remember, the lower the octane, the more energy the fuel has.

Zach

Do what makes you feel better. I will sent my money on other things. 87 for 9 .
years . Runs fine .

At 11.3:1 compression, i always look for the highest octane i can get. Around here, that is 91.

87 octane here

Andy, what do I need to do to find the compression #s on my 2.0? Just wondering....I run 91 in mine and it seems to run great. It's been worked a bit so I doubt it is standard compression.

Jersey - you would have to pull the heads off and CC them. Its somehting you do when building the engine in the first place.
if it runs great, just go with it!

Zach

If it's a stock motor, the compression should be 7.6:1

If it's not stock, Zach already said it, you'll need to cc the heads.