Here's a question I've got as a soon to be '99 L owner. I always run premium U/L of atleast 98 octane in my vehicles and notice the performance bump compared to 94/95 octane. What kind of effect does this have on an L with Superchip? Has anyone ET'ed the difference?

Andrew

 

I believe I'll be moving to Aussie land and taking my L with me. No wonder the 426 Hemi Chrysler wagon I bought while I was down there for a summer ran like a rocket. You sounded as if you simply pull up at the pump for your high octane. Tell me that's not the case...

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Good hunting and check six

2000 Blk Lightning
-superchip
-Downs intake
-one overused gas card
1995 C36
-Schikora chip
1996 VMAX
-Kerker slip-ons
-rejets

 

As of this year Shell has introduced it's new Optimax 98 formula, a nice improvement over the old 95 premium. Before that I was using BP @ around 97 and often throwing in some NOS or 104 plus booster to really spice things up. You should see the shell 98 with some booster thrown in, hold-on .

 

OzFseries,

Here in Las Vegas, Nevada, we can buy 100 octane pump gas at Union 76 Stations. They call it "race gas".

I run it in my cars and it sure keeps knock and spark retard from being a problem. IMHO if you can afford to run the higher octane gas your car will perform as well as it is capable of.

Regards,

Bill

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1987 Buick GNX #424
2000 Camaro SS #1427
2000 Lighting (Red)
1999 VW Turbo Bug
1999 Harley Road King Classic

 

Unless you,ve got your timing advanced, it makes you run really fat, and screws up your performance.
Helps if you have deteonation problems though.

 

While there may be an actual set timeing somewhere in the computer, there is also a knock sensor that will retard timing when knock is sensed. Higher octane gas causes the knock to go away and will allow your computer program to run at its max without being controled by the knock sensor retard program. At the track,, I run a mixture of 35-50% 104 to 93 and it is a definate improvement.
noelvm

 

OzFseries, how is your fuel rated?
Is it: Research Octane (R) or Motor Octane (M) or a combination?
Here in US we us: (R+M)/2
In other parts of the world I know it is common to use Research Octane number with is usaully 2-4% higher. (Most people do not pay enough attention to this to know)

On a side note:
So why are people hearing Detonation?

 

Good question Silver, how the heck are they hearing detonation? Only time I heard detonation is when the wife filled the tank with 87 (not her fault, gas jockey filled with the wrong one), and even then, that was only once. Last I heard detonation was serious, and could be detrimental(sp) to modular engines if not taken care of immediately, something to do with the sonic vibrations or something like that.

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2000 Lightning (Red)
SHM Chip and Mass Air
SHM Blower Pulley
378.2 @ 5100 HP
445.0 @ 3600 ft-lb (before pulley)
Kill Count = 28 suckers picking rubber off their teeth.
SHM powered - www.seanhylandmotorsport.com

'99 Cobra - SHM engine, Vortech supercharger, and to many other mods that my wife don't know about.

 

People with _chips_ are hearing detonation...

Needless to say, the chips are running some agressive timing. But you will get detonation even with a knock sensor if:

1) The computer is not using info from the knock sensor - this seems very weird to me, but 'Inject-tech' said exactly this a while ago

2) Most stock knock sensors can only retard timing a little bit, typically 4-6 degress. If the chips are advancing it more than that (which I'm sure they are)... the knock sensor is powerless.

An aftermarket knock-sensor / retard system would fix this (or reburn the chip).

-DreaminAboutL
'00L

 

In the world of more sophisticated computer programming with knock sensors and other inputs to determine proper timing advance, running a higher octane fuel may be advantageous.

But, I would have to wonder how much advance Ford has programmed in IF all the variables are right. 98 may allow it to run at peak performance, but at some point going too high will not help (unless you have reprogrammed the spark/fuel tables for it).

I know the difference b/w 93 and 105 unleaded is ~45rwhp in my '90 LX...but I also have two different engine management programs for each fuel. If I ran 105 octane in the tank and used my 93 octane program, the car would run worse than with 93 gas in the tank.

Octane by itself does not mean more power. That doesn't mean you can't take advantage of higher octane fuel, though.

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Wes Tarbox
90 LX 5.0 (10.69 @ 134.7)--597rwhp/590rwtq
96 Cobra (12.63 @ 114.5)--390rwhp/441rwtq
99 Lightning (13.20 @ 103.3)--362rwhp/444rwtq
00 Expedition XLT 5.4
http://members.aol.com/Wa2fst/index.html

 

One thing we have to remember here in this thread, and one earlier poster mentined it, is the fact that in Australia they use a different method of calculating octane, and their 98 is roughly equilevant to a 95 octane here in America, where we use the formula: (R+M/2=octane)R=Research method M=Motors method, we simple average the 2 here in America.

SO I have no doubt that running a 95 octane instead of a 92-93 would help a bit, though you quickly reach diminishing returns. We;'ve done specific programs for as high as 104 octane, and only picked up a little over a tenth in the 1/4 mile in these Lightnings. While another tenth or so in an almost 5000 lb. vehicle is nice, the point is it's not a *big* gain going all the way to 104 from 93 octane. Some, but not "a lot". One problem is you have to be careful with the fuel curves versus the burn rate of the fuel, and as you keep going up and up in octane, you can have the motor start "laying down".

Then you have to get into more exotic formulations, to the point that you finally end up with nitromethane in the Funny cars & AA fuelers. They run 95%+ nitromethane, and use 90-120 degrees of initial spark lead and more in those 6000 hp monsters.

Just FYI...........

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Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
Performance Products F150Online Superchip ordering system: F150Online Superchip Ordering System
First National F-150 Online Rally Info:https://www.f150online.com/rally2000/index.html

 

Fooey! I've never seen a car that wouldn't run better and faster on premium gas.
noelvm

 

Then I guess you know more than engineers who design motors.

I've seen this in _practice_ a number of times. I'll use something I'm more familiar with to get the point across.

Take a stock 5.0 Mustang with its timing set like it was from the factory. Running 87 gas will probably net as much, if not more, power than 93. Period. I've seen this on a dyno, and I've seen it at the track. Take the same motor and advance the total timing 6^ from its factory setting and it will ping with 87 gas, and run great with 93 gas (better than using stock timing and 87 gas).

Look above for my other example with a 14psi blown Ford engine. I tune my own cars. I have a decent idea of what works, and I know 105 octane with a spark table set up for 93 doesn't do diddly. Does this mean I set it up wrong? Absolutely not.

Go get some 116 octane gas and throw it in your truck. If it runs better than 94 or whatever...in STOCK form (no chips here) then I'd be shocked. Higher octane fuels have a slower burn rate. That's just one property of this type of gasoline. If you do not take advantage of the slower burning fuel by introducing the spark earlier in the compression stroke, then you will not pick up power, and may even lose some. A lot? No, probably not. But, you're just wasting $$ on gas that can cost up to $6/gal.

Now change the spark table at a minimum and you'll see some significant gains...ESPECIALLY with forced induction engines.

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Wes Tarbox
90 LX 5.0 (10.69 @ 134.7)--597rwhp/590rwtq
96 Cobra (12.63 @ 114.5)--390rwhp/441rwtq
99 Lightning (13.20 @ 103.3)--362rwhp/444rwtq
00 Expedition XLT 5.4 http://members.aol.com/Wa2fst/index.html



[This message has been edited by WA 2 FST (edited 08-06-2000).]

 

Wes, lighten up I agree 116 oct would probably due nothing for the L; however, due to the fact that all engines today seem to have knock sensors in their programming then the 4-6 degrees available can be utilized if premium fuel stops the knock sensor program from retarding timing.
noelvm

 

I don't disagree with that at all...I just didn't get that out of your other post.

My bad.

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Wes Tarbox
90 LX 5.0 (10.69 @ 134.7)--597rwhp/590rwtq
96 Cobra (12.63 @ 114.5)--390rwhp/441rwtq
99 Lightning (13.20 @ 103.3)--362rwhp/444rwtq
00 Expedition XLT 5.4
http://members.aol.com/Wa2fst/index.html