[AR230WAKEBOARDER]

4.50 a gal here for 105

Even stock I notice a big improvement to add 5 gal to a 1/4 tank.

[kujo]

Steve,

When I did my dyno's for the exhaust, with stock ecu and NO cool down period, I poured in 2 gallons of 100.
Mixed with 2 gallons of 91 I had left makes about 95 octane.

I dyno'd 3HP more than my best run.
With NO cool down, so even on the stock ecu, 100 should make at least 8hp at the wheels....

Not easy to feel just 8, but it should.

I got dyno proof the stock ecu adapts.

[SamK]

yeah, look out for fouling plugs, higher octane gas is slower burning and you'll run rich.

[Nyulak]

Octane doesn't make it rich, adding more fuel per unit of air makes it rich. Long life plugs are normally made of platinum and have a short center electrode. This type of design allows the electrode to stay hot, thereby burning off more contaminants from the plug and lasting longer. This type of plug holds more heat and is often replaced for high power applications since the additional plug heat will also contribute to predetonation.

[Revlis]

Originally Posted by zenmaster

What if you upgraded the ignition system to produce a hotter spark?

Burn a Piston...

These motors are so right on the edge already when it comes to timing, A/F Ratios etc... Hotter spark would likely result in something horrible.

This is kind of why I look at all the proceed cars and just sorta cringe... I just I dunno, holding my breath waiting for the great come down at 40k miles when the N54 is destroyed.

Anyhoo, the HIGH octane fuel thing was something the Busa crowd went round and round about a few years ago. Pretty much it was decided that as strange or counter intuitive as it may seem, running OEM recommended Octane makes more power with a lightly modified or stock vehicle.

[Terry335]

Originally Posted by Revlis

Burn a Piston...

These motors are so right on the edge already when it comes to timing, A/F Ratios etc... Hotter spark would likely result in something horrible.

This is kind of why I look at all the proceed cars and just sorta cringe... I just I dunno, holding my breath waiting for the great come down at 40k miles when the N54 is destroyed.

Anyhoo, the HIGH octane fuel thing was something the Busa crowd went round and round about a few years ago. Pretty much it was decided that as strange or counter intuitive as it may seem, running OEM recommended Octane makes more power with a lightly modified or stock vehicle.

Hotter spark resulting in something horrible? You guys are too much. I doubt you can make the spark "hotter", and if you could I doubt it would impact anything

[zenmaster]

Originally Posted by Terry335

Hotter spark resulting in something horrible? You guys are too much. I doubt you can make the spark "hotter", and if you could I doubt it would impact anything

"hot", meaning more energy. It seems that you're not aware that in some cars, the stock ignition system is also something that can be modified with the rest of your tuning. The result of a hotter spark can be more HP in the upper RPM range, and more MPG, for example.

BTW, every time the knock sensor has to retard the timing, damage has already been done to the engine. After all, you're normally not supposed to get predetonation.

I hope these products do not actually depend on the knock sensor being the watchdog for their lean conditions.