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Discussion Starter · #1 ·
The Sunoco near my house sells Octane 100, I was wondering if anyone tried using it on the F yet? B/c I'm about to try it and see if I see any performance improvement..What do you guys/gals think?:D
BTW, it's $8.00 a gal..So I'm looking at likely about $128.00 for a full tank.:eek:
 

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Hey there AO3,
I googled this subject a couple weeks ago and found conflicting info. Everything I read agreed that cleaner fuel (high octane) provides better performance, but alot of the info suggested that the octane rating had to match the dynamics of the engine. Mainly too high octane could actualy reduce performance, not real sure how, but thats what i read. When i owned a 97 supra, a local tech/tuner guy told me to be careful, saying that high compression engines + race fuel (100+ octane) could equal holes being burnt in the pistons. The supra was a 9.5:1 and our F's are 10.28:1 I believe. A local station here sales 100 octane too, I'm thinking of trying 2 gallons added to a tank of 93 octane just to see.
 

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octane rating in gasoline does not increase horsepower. doesn't matter if u run 87, 89, 91, 92, 93, 100, 116.

the octane rating is simply the gasoline's ability to resist detonation by burning cooler. detonation reduces horsepower and causes engine damage. the pistons specifically.

really high horsepower cars run higher octanes because the engine itself needs the octane rating. things like compression ratio, boost pressure, injector size. dictate the octane rating you must use.

i would save your $128
 

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octane rating in gasoline does not increase horsepower. doesn't matter if u run 87, 89, 91, 92, 93, 100, 116.
You're right it doesn't. Any increases in power applicable to an increase in octane rating will be as a result in the design of the engine it's used in, and it's ability to take advantage of the increase.

the octane rating is simply the gasoline's ability to resist detonation by burning cooler. detonation reduces horsepower and causes engine damage. the pistons specifically.
Right Again!

really high horsepower cars run higher octanes because the engine itself needs the octane rating. things like compression ratio, boost pressure, injector size. dictate the octane rating you must use.
Well, here, only partially right. The octane rating, and it's resistance to knock are design criteria that is used in the design of an engine and it's electronics. Modern engines can alter their electronics (read timing) over a narrow range to accommodate various octane ratings in the fuel used. In an engine designed and timed for premium, some will run fine, with a lower power output on a lower octane fuel. The ISF, may or may not run OK on 87. I for one will never find out. Our engine is designed to run on a minimum of 91 octane. 91 is the crap we get in the west. If I had 100 available to me, I would try it in a heartbeat, or as has been suggested, in a blend. I believe the Fs electronics would recognize it and take advantage of it.

i would save your $128
Not me:eek:

Lou
 

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I found it interesting that the manual says 91 is required but if 91 is not available, 89 can be used. I do not ever plan to try that, but it is good to know that it is an option.

I, too, would try 100 octane if I could find it. Seems like the only risk of engine damage would be if you went too low, not too high. But that is just my take.
 

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Discussion Starter · #6 ·
So Lou, you think I should try it? Since some are saying it's gonna hurt the engine while 1 mainly Lou says it will fine..
I'm conflicted here!! Andy please step in and advise!!
 

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I would try it out and use a mix with 93. You'll be fine :cool: I want to find a station around here that offers it to give it a try as well.
 

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I would hazard to guess that the higher the better considering Japan's low grade is typically 93 with the typical high at 98 with 100 avail. When I worked overseas I remember Europe's typical low is 92 and same on the high side as Japan. We get the crap gas at our stations... however much better price.

Personally I only use Sunoco "Ultra 94" unless I am somewhere I cannot find one.
 

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I would hazard to guess that the higher the better considering Japan's low grade is typically 93 with the typical high at 98 with 100 avail. When I worked overseas I remember Europe's typical low is 92 and same on the high side as Japan. We get the crap gas at our stations... however much better price.

Personally I only use Sunoco "Ultra 94" unless I am somewhere I cannot find one.
Europe and Asia measure their Octane differently than the US. They use MON. US uses RON + MON / 2 = US octane. Consequently the US octanes will always be lower than the European and Asian values.

Octane: There is NO benefit to gain using an octane higher than suggested by the manufacturer.... UNLESS.

You have re-tuned your engine (chipped, compression change, turbo, etc.)

Here are some examples:

In my 2002 Porsche 911 the recommend octane is 93. In California the best you can get is 91. Consequently the computer retards engine/spark timing to accommodate the 91 octane and I loose ever so slightly some power. In this case it helps to pump in ~6 Gallons of 100 and ~8 gallons of 91 to give me about 93.5 octane and get optimal performance.

Example 2: You drive a honda civic. It has been tuned from the factory to run on 87 octane fuel. You buy an ECU re-flash to get you that extra 10hp. Now the car is tuned to run on 91 octane. You need to run the 91 octane to realize the 10hp and to keep you motor from pinging.

Example 3: you do the same as above but this time you install a turbo with 26 lbs of boost. You need to run the 100 octane straight to keep your engine from detonating early because of the extreme compression you are seeing in your motor.

Essentially octane makes fuel LESS likely to burn allowing more piston compression to occur before the flame front pushes back allowing advanced timing to occur and make more HP.

If your car ECU does not have air/fuel/timing maps in it for fuel with the rated octane, it cannot take advantage of the octane. Some modern cars (I assume the IS-F is included) have sensors (typically dual knock sensors) that allow timing to be advanced just until the edge where knock is detected. This maximizes power. However if your ECU maps do not have info for 95-100 octane, then you will see no benefit.
 

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So Lou, you think I should try it? Since some are saying it's gonna hurt the engine while 1 mainly Lou says it will fine..
I'm conflicted here!! Andy please step in and advise!!
uh i never said it would hurt to use higher octane. i said it wouldn't give u any more horsepower. it would be a pointless investment
 

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It should not hurt the engine. But you will loose benefit on anything over 94-95 octane, so save some money and mix it. It is a linear mix.

15 gallon tank: (5gal x100oct) + (10gal x 93oct) / 2= 95 octane
 

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Discussion Starter · #13 ·
Over here in Qatar we have 97 octane and the full tank is for only 15 bucks :D
I'll paypal you $100.00..Send me $100.00 worth of octane 100's..:D:D
 

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Over here in Qatar we have 97 octane and the full tank is for only 15 bucks :D
its tidbits like this that piss me off. canada makes more then enough oil to support itself but it ships 2/3 of its production to the fucking americans. and on a liter/liter, gallon/gallon conversion we pay roughly 30-40% more for the same amount of gasoline. then theres places like, the middle east and Venezuela that practically give the shit away. ie. 12 cents PER GALLON. like fuck me sideways. i'll buy an entire fuel tanker load for $1100.

then basically everywhere in europe is double or tripple what it is in north america............

i'm going to bed before i murder someone...
 

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I am running 100 Octane in my F as well, and must admit that I like the feel. Given the fact that most of these cars are fitted with "knock-sensors", the higher octane gas would in all likelihood prevent the computer from ever cutting timing, thus allowing the car to operate at the highest level of performance.

BTW...It is only $5 a gallon here in N. California.


The Sunoco near my house sells Octane 100, I was wondering if anyone tried using it on the F yet? B/c I'm about to try it and see if I see any performance improvement..What do you guys/gals think?:D
BTW, it's $8.00 a gal..So I'm looking at likely about $128.00 for a full tank.:eek:
 

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Europe and Asia measure their Octane differently than the US. They use MON. US uses RON + MON / 2 = US octane. Consequently the US octanes will always be lower than the European and Asian values.
Well that sent me on a trip to the wiki website. I stand corrected. The US / Can octane systems aka "AKI" is basically. Europe uses RON (research) aka headline octane (not MON). My understanding is that in easy calculations US/CAN = .95 RON. Therefore the range is similar of 87 to 93. At the same time they have RON octane levels up to 100 and 102 which results in what we understand as 97 AKI octane level. But I guess we can get 100 AKI... interesting to me now that I understand a little better...
 

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its tidbits like this that piss me off. canada makes more then enough oil to support itself but it ships 2/3 of its production to the fucking americans. and on a liter/liter, gallon/gallon conversion we pay roughly 30-40% more for the same amount of gasoline. then theres places like, the middle east and Venezuela that practically give the shit away. ie. 12 cents PER GALLON. like fuck me sideways. i'll buy an entire fuel tanker load for $1100.

then basically everywhere in europe is double or tripple what it is in north america............

i'm going to bed before i murder someone...
Ouch...

Just remember our wonderful gov't (feds/prov.) add 35% in taxes on average and in the states about 20%. Plus we have excise taxes and GST in around that too. So when you pay $.80 at the pump it really should be $.60 (2.28/G). In my opinion we got to get our gov't to stop hosing us at the pumps before we blame our neighbours to the south. That and pump price fixing.

It would be nice if the royalties on our oil were significantly increased so we can pay less taxes and have subsidies on fuel especially considering Canada has the 2nd largest oil reserves in the world! Our royalties are the lowest of developed nations!!!
 
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