Is it safe to run a higher octane?

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I've only used 93 octane in my stang and have 10,000+ miles on it. I also only go to gas station thst offer gas with additives like Chevron and Shell to help keep the injectors a little cleaner.
 
Without a new tune, running a 92/93 octane on a car will waste money.

I did actually remember somebody saying that running a higher octane than your tune is designed for can actually be harmful.

Now, if you get your car tuned for a higher octane, then it should be fine and you'll get more power. However, using a higher octane w/o a new tune will not give you more power - may be less power actually. Now, I wouldn't go crazy and use aviation fuel that's more than 100 octane - your engine will not like that :D
 
Fuel

Here we go again. I'm sorry but burning high octane fuel will NOT cause any harm-I don't know where this idea came from but it's wrong. That being said, you might not get enough of a gain to justify the extra cost, but it won't hurt anything. I have read in more than one place that the new Spanish Oak computer in our cars will, because of the knock sensor, slightly advance the timing with high octane fuel which is supposed to give maybe 2-3 HP more-certainly not enough to beat your buddy's Z06 but a slight gain. I have experienced something on all 4 of the V-8 Mustangs I have owned and that is the engine idles smoother with premium fuel. Premium fuel contains more detergents and this will help keep those expensive electronic injectors clean. One last point-many people report getting a few more MPG with premium fuel. Your car will, indeed, run just fine on 87, but if you want to and don't mind the extra cost-go for it. :nice:
 
GOLDENPONY said:
Premium fuel contains more detergents and this will help keep those expensive electronic injectors clean. One last point-many people report getting a few more MPG with premium fuel. Your car will, indeed, run just fine on 87, but if you want to and don't mind the extra cost-go for it. :nice:

Well spoken. The above quote is the only reason I run 93 octane. I don't believe that I'm gonna get horsepower from the octane gas I put in but the added detergents in the 93 with help keep my engine running cleaner and longer. That is why I spend the extra couple bucks at fill-up time.
 
GOLDENPONY said:
Here we go again. I'm sorry but burning high octane fuel will NOT cause any harm-I don't know where this idea came from but it's wrong. That being said, you might not get enough of a gain to justify the extra cost, but it won't hurt anything. I have read in more than one place that the new Spanish Oak computer in our cars will, because of the knock sensor, slightly advance the timing with high octane fuel which is supposed to give maybe 2-3 HP more-certainly not enough to beat your buddy's Z06 but a slight gain. I have experienced something on all 4 of the V-8 Mustangs I have owned and that is the engine idles smoother with premium fuel. Premium fuel contains more detergents and this will help keep those expensive electronic injectors clean. One last point-many people report getting a few more MPG with premium fuel. Your car will, indeed, run just fine on 87, but if you want to and don't mind the extra cost-go for it. :nice:
:stupid:

I agree. There's no harm in running higher Octane fuel, however to get the best of it a tune is needed. I would have thought that the ECU on the new Mustang should advance the timing allowing a little more BHP and better throttle response.

I recently watch a test on octane ratings. On 3 different cars:
-small city car 1 litre
-family hatch back, VW Golf (1.6 or 2.0 litre)
-Subaru Impreza Turbo

Going from 95RON to 97RON (about the same 91PON to 93PON, which is the octane rating you guys in the US generally use).

City car - No change
VW - small increase, less than 4bhp
Impreza - nearly 20bhp and a lot of torque.

FI cars do like the higher octane and I guess the Subaru's ECU had a far amount of control.
 
I think it is a big mis-conception among people that there are added benefits to running higher octane fuel.

I can find more documentation showing that higher octane fuel may actually harm an engine that does not require it rather than helping. The only exception that I am aware of may be in today's computers.....if they advance timing when higher octane fuel is used, then there may be power benefits. However, i believe that if timing is held costant, there is no benefit in using higher octane fuels.

This is a subject that comes up a lot in car circles and I've never seen a good explanation or documentation showing that running higher octane fuels than what your vehicle requires is beneficial. For those that want to read more, check out a few of these links.

http://www.ricehatersclub.com/vbulletin/showthread.php?t=9836

http://en.wikipedia.org/wiki/Octane_rating

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

If someone can find documentation or has an explanation to the contrary, I'd be interested.
 
I haul gas and can tell you honestly that Chevron's premium DOES contain a higher percentage of Techron ( that's the stuff that cleans everything) So that said, it does help to run it just to get the extra Techron in the gas, but Chevron's regular and midgrade also contain Techron, just in slightly lower percentages. What I do is run premium in my vehicles about once a month just to keep things clean, all other fill ups, I use whatever's cheapest. Texaco gas also contains Techron, but I don't know for a fact that it's the same mix as Chevron-branded gas has. Also pretty sure Shell has it too. But you don't have to buy these three brands to get Techron, you can buy it off the shelf at many parts houses and add it yourself. I tried a tank of half-n-half regular and 93 octane premium (Texaco) that resulted in about a 90 octane mix, but found no difference in performance or mileage over 87 in the new Stang. On my 89 Ranger, when it was new, switching octane did make a difference in mileage, but I got the same from 89 as I did with 93, which was ( if I recall correctly, it's been awhile) about 4 mpg.