Man, what a difference gas makes. Yesterday I stopped to fill up and the station I go to was out of 93 octane. No problem. I put 10.00 mid grade in just to get around for a couple of days. Big mistake, it knocks, won't shift right, won't run as good. My advice is to do what superchip says and burn 93.




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Mike Kimbro
1999 F-150 Lariat, 4x4, SC, Flareside, 5.4,White/Tan leather, CD changer, Flowmaster 40 series, K&N FIPK, and Superchip

 

Hi Mike,

Another thing that affects this is thw actual energy content of the fuel being used, as somtimes the octane number will be there, but the BTU content just isn't.

There is also a good bit of variance in the total effective compensation range of the knock sensor systems. There are some of these F-150's that can go all the way down to 87 octane with the Superchip and not exhibit detonation, you just lose the power gain and it won't run as smooth, of course. Then there are others that cannot drop to a mid-grade wihtout pinging, as you experienced, so it can be energy content combined with the knock sensor system in your particular vheicle that affects all of this.

The bottom line is you're absoltuely right, you'll get the best results by far using the Superchip with premium gas, just as it was designed to be used with, due not only to changes in the timing curves, but also the changes in the fuel curves necessary to compensate for the burn characteristics of premium gasoline, it's always going to run better on premium with the Superchip.

Thanks for your post!

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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 Event Organizer

 

what is detonation?
i am pretty sure we arent talkin about a big kaboom! under the hood, right?! j/k

seriously, i never understood what detonation was or why it hurts with lower grade gas

 

Take a tin can and put a small nut in it. Shake the can a little bit. That will sound something like detonation.
In a vehicle you will get this sound when you get on the gas pretty hard and do not have enough octane or ignition. You can also get detonation when pulling up a hill. Seems like the timing is off.

O have a friend with an F-250LD with the 5.4 and a Superchip. He uses 87 octane and I keep trying to tell him use 92 octane but he wants to save the money for Mich Light.


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97 F-150, 2WD, Reg Cab,Flareside,Dk Toreador Red, Windsor 4.6, Magnecor 8.5mm wires, Bosch Plat +4s, 3.55 LS, EGR Bug Deflector, ******* Bed Cover, Bed Liner, XL Full Length Running Boards, Air Aid Kit, Gibson Single Out Cat Back, Superchips, TransGo Shift Kit, Hellwig Rear Sway Bar, Hellwig 2500# Overload Springs,Energy Suspension Polyurethane Front Sway Bar Bushings, 265 70 16 tires, Rancho RS9000 shocks

 

HI Cool,

Detonation, sometimes referred to as "pinging", or "pre-ignition", has several forms, and several different potential causes.

The most common form of detonation is pre-ignition, where the air/fuel mixture is ignited too far before the piston reaches TDC (top dead center), caused by too much spark advance for the octane level of the fuel being used. The cure is to use a higher octane level of gasoline in that situation.

Detonation can also be caused by a lean condition, especially in forced-induction motors (meaning supercharged or turbocharged), from not enough fuel in the air/fuel mixture, referred to as a "lean" condition. In that case you have to add more fuel to the A/F mixture to cure the lean condition and eliminate detonation.

You can also have detonation even when you're not running lean and the octane level of the gasoline being used is high enough. This is caused by the gasoline not having a high enough **energy content**; gas is rated in terms of the number of BTU's per lb. or gallon of gas. Sometimes "reformulated" gasolines will not have a high enough energy content, and thus will not support the same conditions in the combustion chamber, and you get detonation, or uncontrolled combustion in other words. In that case, you simply have to use a higher-quality brand of gasoline.

The actual sound of detonation is kinda like marbles rattling around in a coffee can under the hood. T. Ellenberger's description of what detonation sounds like was very good also.

I hope this info helps,

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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 Event Organizer