What is the difference in 87 octane and a 91-93 octane tunes other than the ignition timing? Retard for 87 and advance for higher octane.

Now that the timing can be changed within certain RPM ranges Example 2000 to 4200 / 5000 to- 6500 and have global timing also that covers the whole RPM range how does that all work in conjunction.
My old motor head needs help in understanding why we now need this and what is the timing per octane degree difference is. How about an Expers answering this puzzling question. Thanks in advance.

 

For what it's worth, 5.0 Mustang magazine in the latest issue mailed to me yesterday reported that Ford is relying on the Knock sensor to pull back timing for low octane gas and the fuel table that is in the computer is actually a premium octane program. Whether 91 or 93 I don't recall if they said.

How does this affect after market tunes and what they are programmed at, I have no idea.

So, the easiest upgrade so far is running premium gas.

If you're running a tuner that has diagnostic capability you can always keep bumping the timing up untill you see the knock sensor kick in.

Personally I'm running I drive around with a 91 octane tune using 92 gas. On track days I either get race gas or run NOS racing octane booster, put in the 93 tune and bump the global timing. It worked in the cold air, don't know how that will do with the hot weather we have now.

 

Chris,
Where do you find this 93 octane tune for the Predator? I have the C&L and Predator and can't find this 93 octane tune.

 

My 93 octane tune on the Predator is listed as "Performance Tune". I had some small detonation, especially in the higher RPMs, that the spark advance/retard wasn't fixing. I figured it was running a bit lean (no access to a close dyno), so I slowly added some fuel at WOT. Fixed the detonation and actually made the seat of the pants feeling much better. I don't have a CAI, just a K&N drop in filter and HC removal.

 

the 93 octane tune for the C&L is the C&L tune that doesnt show an octane rating when your choosing which tune to upload onto the car. BTW-these are the C&L tunes you should have Downloaded onto the predator before tuning.

 

Awesome, I did not know that. Looks like I'll be retuning my car in the work parking lot before I go home.

 

Are you able to get 93 octane gas? I had to go back to 91 octane tune.. with the 93 octane tune I had ping at around 4500 WOT. I only see at best 92 octane gas regularly. Another reason to stick to the 91 octane tune.. road trips and the ability to at least get 92 octane .

I am interested to know how it worked out for you...

 

We've got an abundance of 94 octane around here...