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Discussion Starter #1
I was just wonder what octane other bullitt members use. For my daily driving I use 89 Octane but at the track I use 93 Octane.
Has anyone tried any octane higher than 100??

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anumis

Black Bullitt #1574
Gigabeast Dot Com

<font size=-1>[ This Message was edited by: anumis on 2001-09-10 15:33 ]</font>
 

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I use 87........car runs fine!!
 

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I run 89 in mine. Never tried 87. It was June when I got the car and HOT so I notched it up one grade.
 

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The engine is made to run at 87 and that is what I use. The only reason I would change is if I put a chip in.
 

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Higher octane gasoline offers no performance improvement. It should only be used if your engine knocks.

Engine knock occurs when the air/gasoline mixture in the cylinder explodes prematurely. Our engines have a normal compression ratio (9.4:1), so 87 is perfect. If your car has an engine with a higher compression ratio, like a Cobra (9.85:1), then it might knock with 87 octane. The reason the Cobra gets more power is because its engine has a higher compression ratio. A side effect is that it requires higher octane gasoline.

basically, higher octane doens't mean better performance. Higher compression ratios means better performance, but requires higher octane gasoline.
 

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Thanks for the suggestion nasty. With me I think it's one of those emotional sucker things...given three choices I just haven't been able to put the lowest grade in. What brand are you using? I've been running Chevron only.
 

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I've been running regular octane also but once I get the densecharger, alum. driveshaft, x-pipe, and underdrive pulleys on I plan to have it dyno-tuned and get a custom chip burned. I expect that I will be running 93 after that.
 

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Discussion Starter #9
I guess I will switch to 87 octane instead of 89 since I really do not need the higher octane since my bullitt is still stock. Thanks guys
 

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Interesting? ARCO seams to be the low end of the spectrum down here too. Didn't know anyone made 85 octane gas! I'll have to watch out for that on road trips! Glad you caught that one...would have been a bummer buring down enough gas before tanking up with better stuff.
 

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87 octane for me, Chevron only. Have tried Unocal, Shell, Arco, all seem to not react as well to the Bullitt like Chevron. Maybe Chevron puts something in there gas. With Chevron the engines seems to run much smoother and sound smoother.


Mike
DHG #3463
San Ramon, CA.
 

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My $0.02:
The purpose of octane is actually to slow down the burn. Higher compression creates much more heat in the fuel mixture and will actually detonate the fuel in an uncontrolled burn without the proper octane level. (Diesels with 18 to 1 compression don't even use spark once the engine is running).
The Bullitt's compression ratio should never need higher than 87 as long as the factory specs are intact (timing & mixture). In fact, due to the retarded burn, higher than 87 octane on a factory spec engine could actually result in a slight loss of power, not to mention a waste of fuel dollars.
 

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87 and have tried 93 for a couple of tanks. If there's any difference not much difference but if anything, runs better on the 87!
 

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Chevron 87 has been fine so far.

BTW: Diesels don't spark period - no spark plugs, no coils, distributors or any of that other ignition hardware. They ignite stricty due to pressure. Some do have glow plugs, but they are only to raise the temperature of the air entering the chamber for easier cold starts.
 
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