i have been using premium since my purchase and just noticed the "reg. fuel only" on the cap. will higher octane fry my valve heads? im about 9700 miles. should i be worried? thanks.

 

I've never had any problems.

 

it shouldn't, i ran with 91+ octane booster about 97 and my car is fine and with higher octane is better for you car. if you don't put desiel

 

Standard high octanes here (varies from station to station) are 91 or 93 octane. My normal station's 93. Absolutely no complaints whatsoever.

 

Yeah I was wondering if we could do that. I was skurd to put higher octane gas but since yous guyz have no problems with it...and since its good for the car, might as well start putting it in.

 

with the normal na setup, higher octane is not good for your car. It has no benefit whatsoever except leaves you with less money, you don't need to use higher than 85 (yes 85, that's what we get waaay up here) until you do some forced induction or other methods of increasing boost (nos)

 

Doesn't higher octane fuel also tend to burn cleaner? I'm not lookin' for performance mods.

 

No, it DOES NOT burn cleaner. The "Premium" designation is just a gimmick to clean your pockets. High octane fuel is only needed by V8's, forced induction cars, race cars or if you're into laughing gas (NOS). I've only seen only one responsible gasoline company advertising 93 octane fuel as a necessity for V8 cars (they used a Crown Vic on the ad) and that was a couple years ago. The typical 4 banger or V6 will run perfectly with 87 octane fuel and no difference in performance will be experienced. Octane ratings merely state the ideal temperature and/or conditions at which the fuel will combust (explode, burn). Our cars are factory tuned so the ideal combustion be made with regular fuel. Conclussion: using higher octane fuel on your car is a waste of money.

 

Just regurgitating something said in another forum by somebody else... supposedly, use of a higher octane gas in this engine can burn up (?) the valves or some ****. Basically, the way the engine was set up, in order to get more fuel efficiency, they set it up to use only regular fuel... in other words, it could be that with continous use, it could cause problems. Like I said, this isn't first hand information at all, just something someone else posted. But, supposedly, you use it every once in a while, it's no big deal, just not week after week. But, really, I'm not positive.

 

Okiedokie, he's a seemingly good link. If nothing else worth the read for confirmation.

<click>

 

Running higher octane in our car is fine. It wont do the car any harm, it will just leave you with a smaller wallet

 

We recently went from 93 octane to 87 octane in our Ford Crown Victorias. My patrol car now has a WHOPPING 13k Miles on it and the valves rattle like all get out with the cheaper gas. Granted this is a V8. Just thought I would pass it on.

 

The only time changing octane levels is bad for your car is if you use too low an octane for your car's engine, e.g.- using regular fuel instead of premium. A friend of mine had an Eclipse GSX and did this... he blew the engine in less than a month. Says he didn't know what the difference was... Anyway, getting back on topic, higher octane might actually be better for your engine but it's not better enough to justify spending the extra cash if your car doesn't call for it.

 

OMG, used regular on a GSX. It must have killed the knock sensor for the TC'er and retarded timing beyond spec . . . before its death toll.

The great debate. It varies if you have slushbox or manual. Manual, you might not feel the differnce at WOT. On a slushbox, you can tell that it has a bit more "ump" merging on the interstate.

The same for Magnecor wires . . . same as above great debate.

 

Late to this post, but found it interesting.

Using gas with an octane rating higher than specified by the mfg can be bad for the car in the long run. Octane rating essentially relates to the resistance of gasoline to ignite and burn in a controlled fashion against temperature / combustion chamber pressure. The lower the octane, the more readily the gasoline ignites and burns, the opposite with a higher octane gasoline.

On a NA engine with fixed ignition timing where a low octane is specified, a higher (like 93) octane gasoline may not burn as completely during combustion as the lower octane gasoline would, which can contribute to forming deposits on your heads, valves, pistons, etc.

On NA vehicles equipped with engine controls and knock sensor(s) , the ECU or "brains" can advance the ignition timing by lighting off the mixture with the piston closer to TDC - meaning a higher pressure exists within the air/fuel mixture before a spark is introduced. Here is where you can get the (small) additional benefit of using a higher octane gasoline.

After wasting more than a few $ on premium gas over the years, I always start by burning the octane grade recommended in the owners manual. There shouldn't be anything but an occassional light ping or spark knock from the engine once in a while, unless the place you fill up from has crap for gas. If it's hot as hell out, or you're towing something (not with the Lancer anyway), you might have to go up one grade to prevent excessive pinging.

You'd be better served to save $ by using 87 octane and throw a can of BG Products Total Deposit Control in your tank once every 3,000 miles. It's a preventative maintenance type product which removes deposits before they accumulate and cause problems later.

And yeah, "diesel" wouldn't burn too well in there at all

 

Um.. NO.

A stock motor utilizing the octane recommended by the manufacturer should not ping or knock. Ever. Doing so is a sign of incomplete combustion or pre-detonation. Both are problems, and both are bad.

-M

 

i notice a difference in my car with 87 and 92 oct gas with 92 i get smoother faster acceleration 87 isnt as great and is slower but i do get better gas millage on teh same trip with 87 and im not trying to start some fight that is just how it is with my car

 

So you'll NEVER ping on recommended octane - hmmm....

Take the car filled with 87 octane to Houston in the middle of summer. Drive through stop and go traffic on the I-10 freeway at afternoon rush hour in July or August.

You'll get pinging since the baked asphalt and heat coming off cars around you elevates the intake temp to about 115 deg F. The air temp is elevated enough that the 87 will ping in an engine without a knock sensor and mechanism to retard the ignition timing. If your car does have an ECU that can adjust, you'll notice how doglike acceleration will be since the ignition timing will be retarded to whatever is the maximum allowed by mfg design in an attempt to eliminate spark knock.

While living there for two years with a different "new" car it was immediatelty noticable - hell it was so hot a few times that even on 93 octane it would ping lightly under such circumstances.

Constant pinging is bad, but not a once in a while thing, for the reasons described here.

A useful link:

http://www.ftc.gov/bcp/conline/pubs/autos/octane.htm

 

Okay, point taken. Under normal operating circumstances, your car should never ping using the recommended octane. 115F is not normal... Though, we had a 112F day here about a month ago, and my OZ was just fine, even with the AC on full blast, using Chevron 87.

-M

 

I agree..I feel the same too..& I am with 93.