Local airport has 100 octane gas, would it be harmful to run?
 

So, as the title suggests, the local airport has 100 octane Low Lead aviation fuel for about 4.80 a gallon. I'm curious if it would be harmful to run in this engine. I've run the gas before in my dirtbikes with no ill effects whatsoever, but I'm assuming with three extra cylinders it would be a different story.

The engines used in all the Cessna's are all horizontally opposed 4 cylinder engines, so they are somewhat a close cousin to the engines in these cars. I know it says unleaded fuel only but I've never quite understood why and if it would be harmful to run a low lead gasoline in the car. Any help would be appreciated, and if this thread needs to be moved please do so mods.

Why would you want to?

you'd have to remove the cats to run leaded fuel!

Because racecar :burnrubber:

(Sorry, had to :lol:)

Lead contaminates and reduces the effectiveness of the catalytic converters, it also coats the O2 sensor rendering it useless in a much shorter time period.

Long story short, long term drawback probably not worth short term gains

Most Cessnas run horizontally opposed engines, yes. However, they run carbureted, low compression (~7:1), air-cooled horizontally opposed six cylinder engines that have a design dating back to about the 1940s. Your engine has very little commonality with the aviation engines aside from which directions the pistons travel.

Oh, and definitely don't run leaded gas. You can find race gas some places if you really have a hankering to run high octane. You won't gain anything from it though unless you have made other modifications as well.

I think I should state again that I'm not necessarily saying that I'm going to start pouring the blue stuff into my tank, I was just simply curious. Just trying to understand all the mechanics better! :thumbsup:

Higher octane won't improve anything over what the engine is designed to run on.
A higher compression ratio may warrant it, but the lead is not a good idea.

Wasn't speeding officer, only flying really low.

No, don't use it. Check with your local Sonocos as they are somewhat likely to carry race gas. However, I think you wont notice much other than the nice smell.

Here's the VP race fuel distro for Oregon. http://repowell.net/vp-racing-fuel.html

Lead will damage the catalytic converters($$$$). It's part of the reason lead was banned from Gasoline in the 70's.

Either look for unleaded race gasoline or E85. Don't forget the ECU tune.

Lol.

If you are in Portland there is a gas station off of MLK up by PIR that sells pure 93 octane (no ethanol) and 107 octane sonoco race fuels.

100Low Lead has 10 times the amount of old leaded car gas. It fouls out the plugs in aircraft engines that run at 65% power or more. Auto engines would foul out even faster. On top of ruining the cats and fouling out the O2 sensors, it gets in the oil. we change piston aircraft oil every 35 to 50 hours of flying and it is nasty when it comes out. We used to run airport cars on 100LL and they didn't last long after we started using it in them. Rotax makes a H4 that will run on auto gas or 100LL. We have found when ran on auto gas, the internals of the engine are cleaner.

John

I'm a pilot. We call 100LL "100 Lots of Lead". It's call LL because it has less lead then the Green 130L that it replaced in the early 1960's.

Moreover, besides having way too much lead for the O2 sensor and cat, 100LL isn't formulated for throttle response - it's formulated for long storage life.

Interesting.... So if you run 87 then your car is gonna run like crap, if you run 100 octane then your car is gonna run like crap(eventually), but if you fill it up with 93 your car is race car clean. Bad joke

Not necessarily, it's the leaded part that will cause problems, 100 octane will probably be ok if it's a "standard" blend.

Of course, our cars don't have the compression ratio and ECU tuning to take advantage of the 100 octane (stock) so it's kind of like throwing money down the drain if you have 93 readily available.

I have used 107 Octane "unleaded" fuel for racing and autocrossing in serveral Subaru's going back to the 90's. It will not hurt your car, but it might not give the benefits you hope for. I found it gave me slightly better performance and would just take 5 gallons (in a racing canister that was molded plastic) run the car down as empty as I could before the event and then put in the 107 octane. That is the only times I ever used it. One quarter of a second in a timed competition event was worth it. But I would never use it for street driving as the difference was not worth the cost or trouble.

I would never put leaded gas into a 2013 car with a standard manufacturer engine. It will cause you much more trouble in the long run than you will experience any performance increase in the short run.

If you're running leaded-anything, even if it's 1000 octane, you'll do more harm than good if your internals are stock and you're running factory timing.

If you have an engine built up to run this type of gas in the first place, you wouldn't be asking the question.

The only benefit of running fancy high octane gasoline, is the feeling that you're a much faster driver with it. It's like putting on stickers on the car... you look and feel fast, but it doesn't add any power to the car.

And costs money.

Sidenote: yes, high octane gas may help at the track under extreme temperatures, but frankly if the temps are so high where a stock engine warrants such high octane gas, I'd be more worried about cooking the brakes/tires/coolant before engine knock becomes a major issue.

-alex

How? Unless you're running identical back-to-back with the same vehicle weight, tires, ambient temps, etc, just increasing octane alone will not improve performance unless your engine was modified to take advantage of the higher octane (usually in the form of more advanced timing.)

But then again, it all depends on what gas the engine was originally tuned for.

-alex

Why did this remind me of the Family Guy episode where Peter thought about putting airplaine fuel in his car? But you never know until you try so . . . . . . . .

That was how I used it. For autocrossing events or track days.

I had a 2.5RS with Cobb tuning upgraded camshafts, Prodrive cold air intake and cat back exhaust,. As well as a mix of Cobb, Prodrive and STI perfromance parts in the suspension, transmission and shifter.

I tried to say that I thought it was not worth the trouble, effort or money to use on a daily driver to try and get more perfromance. Guess I did not do it well.

I've run 100 octane unleaded in my tank a couple of times. Not sure if the car was any faster, but it sure seemed to run smoother. 8-9 dollars a gallon hurts though.

Running leaded fuel causes brain damage and criminality. No kidding. Leaded fuel goes away. Crime rates drop as the last brain-damaged cohort goes away. Leaded fuel is poison. Stay away.

lead will kill the cats and possibly other sensors.
tha additional octane won't help you unless you modify the ECU
to take advantage of it.

[ame="http://www.youtube.com/watch?v=A6ZklI4D5Ko"]family guy jet fuel truck - YouTube[/ame]