[Pony XTC]

November issue of car & driver mag. did a test on a new 260HP Mustang GT. The test went like this.....87 octane gas vrs. 92 or high octane gas. Their test showed an absolute increase in HP by 2 with the 92, however, the 1/4 mile runs were better with the high test by a whopping .3 of a second. That tells me high octane gas is the difference between 14.20 and 13.90 in the runs. I don't know about you, but for a couple bucks a tank, I'll take the high test!!

 

[CatSmasher]

I smell something, and it aint gas!

 

[Pony XTC]

Never underestimate the computers in these Bullitts, I really believe they will compensate for lean, rich, ping etc. Timing will be adjusted. Ford motor company rules.

 

[rancorkeeper]

Unless that engine was having pre-detonation problems, there's no reason different octane is gonna make that kinda difference in 1/4 times. 92 or 93 octane isn't a power adder & our engines don't have high enough compression to require a higher octane.

 

[MOLJAY]

That also matches up with what the manual says. It actually says not to run premium, and that it can actually harm the engine. I always run regular unless I hear knocking or pinging, and so far I haven't heard anything except that wonderful throaty roar! :smile:

:bullitt:

 

[Pony XTC]

If the computer adjusts your timing when sensing the octane, you WILL get a performance increase. Why chance it for a few pennies a tank more. Besides I think the car runs a little hotter on reg. Hey this is the 21st century, nothing is impossible.

 

[JB VOBRA]

this is easy:

car not pinging on 87...leave it alone

car pinging on 87...fill up with 89

car pinging on 89...time to take to Ford and get computer reflashed because something is not right.

 

[Barnaby]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-10-16 18:22, Bullitt XTC wrote:
If the computer adjusts your timing when sensing the octane, you WILL get a performance increase. Why chance it for a few pennies a tank more. Besides I think the car runs a little hotter on reg. Hey this is the 21st century, nothing is impossible.

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>
If it doesn't have a knock sensor then how would it sense a difference in octane? Answer, it can't.

I would read through the magazine very carefully to see if they now have oil companies advertising in it. That would explain their desire to show a huge increase in performance to it's readers.

 

[schmedlap]

The way I understand it......the computer will not adjust timimg to octane unless it is programmed to do so. If you put a SuperChip in, the computer is programmed to run 90+ octane and your timing is advanced! I doubt the mags credibility.

 

[rancorkeeper]

As far as the computer "sensing" a higher octane, it can't, even with a knock sensor. The computer has to be told the car is running on a higher octane gas. You could put kerosene in the gas tank & the computer wouldn't know it; it would just know something was wrong & probably retard the timing. What a knock sensor does is adjusts the air/fuel mixture because it's hearing more knock than usual. It can't tell whether there's a higher octane in the fuel, either. Again, this all relates to knocks or pings & if you hear them, you can put in 89 or 92 if you like.

 

[Pony XTC]

How can you people not believe the tests? Read the magazine. High test gave that GT 3 tenths in the quarter mile!!!!!!!! When you do the same test then you can talk. All of you are old school talkers who won't admit they may be wrong. Can hi-test hurt your car? I think not. How can you afford not to at least try it? I mean after all, everyone of you bought this car for high performance right? When my Bullitt outruns yours by an eyelash you'll know why!

 

[Barnaby]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-10-17 08:19, rancorkeeper wrote:
As far as the computer "sensing" a higher octane, it can't, even with a knock sensor. The computer has to be told the car is running on a higher octane gas. You could put kerosene in the gas tank & the computer wouldn't know it; it would just know something was wrong & probably retard the timing. What a knock sensor does is adjusts the air/fuel mixture because it's hearing more knock than usual. It can't tell whether there's a higher octane in the fuel, either. Again, this all relates to knocks or pings & if you hear them, you can put in 89 or 92 if you like.

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Right you are. What a knock sensor can do is sense whether there is a predetonation and retard timing or adjust air/fuel ratio accordingly. My bad for stating that it senses octane.

 

[JB VOBRA]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-10-17 09:08, Bullitt XTC wrote:
How can you people not believe the tests? Read the magazine. High test gave that GT 3 tenths in the quarter mile!!!!!!!! When you do the same test then you can talk. All of you are old school talkers who won't admit they may be wrong. Can hi-test hurt your car? I think not. How can you afford not to at least try it? I mean after all, everyone of you bought this car for high performance right? When my Bullitt outruns yours by an eyelash you'll know why!

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>

uh, I'd say I have room to talk XTC. To my knowledge, NO one has run faster times in a stock Bullitt than me. And I've experimented with different grades of gas at the track. Guess what:

the fastest trap speed I've ever run was on 87 octane. 101.83 trap.

Am I advocating 87 octane even if the car is pinging? Of course not. Run the 89. But I'll tell you this, turning into a magazine racer and believing all their hot air is a real poor choice. They tend to leave out "minor" details like "was the car cooled the same duration between tests?" or "had the outside temp dropped 15 degrees between test runs?" or "the test driver finally got traction and busted a launch".

These kinds of factors could EASILY account for the difference in times.

 

[rancorkeeper]

I agree 100% with JB about believing magazine articles: Don't! & as for being an old-schooler, let me give you two examples (both Chevy's, but relevant). My 1970 BB Monte runs ABSOLUTELY FINE on 87 octane & it has 10.25:1 compression. There's no power difference with a different gas, unless it's very hot or humid, which effects cylinder head temps & causes pre-ignition (or unless it's 104 race gas). My 1994 LT-1 Caprice has the computer reprogrammed & an LT-4 knock module & runs no differently on 87 or 93 octane. These are my experiences & I think I have infinitely more experience on the strip or under the hood on both of these cars than most casual enthusiasts. My point is, carbureted or computerized makes no difference: Minor octane differences WILL NOT affect performance like the article describes. Period! We don't need to test it in the Bullitt 'cause we know this to be a fact. Read up a little on octane ratings if you don't believe any of us. I'd be more than willing to find some web sites with good descriptions & definitions if you'd like. That's what I like about these forums. It gives people a chance to talk with others who know more about certain subjects & learn something. Personally, I've learned a ton about fuel injection, computers & ABS over the internet in the last few years.

 

[Rob00GT]

Sounds to me like they turned off the traction control for the second (faster) run.