= no more pings, not more power.

When the car is pinging doesn't the timing get adjusted to minimize the ping? When the higher octane gas is used and the precombustion is reduced, the timing should be re-adjusted back to a more optimal setting...providing more power.

lemme know if I'm way off on this one =)

-Brent

but he'd have to be pinging with 93 right?, and the move to 94 would be enough to stop it?. I've never had trouble with 93.

I have no clue, I just have a gut feeling that a 1 point octane difference would be perceivable in any (non race) vehicle, especially one equipped with an automatic.

fwiw
slack

went from Exxon 93 to Sunoco 94..

Just picked up my MY2000 Avant w/SportPackage 1.8T. (approx 700miles)
This car is INCREDIBLE !
I have noticed, however, that off the line accelaration (in 1st/2nd gears) tends to be somewhat
lacking, especially when compared to acceleration at high-way speeds. I guess I feel it should be accelerating faster at these lower gears...are you getting the same impression. Sunoco 94 definitely seems to be doing some of the trick, but I'm wondering whether a 'chip' would help w/the extra boost....what are your thoughts?

ive been a sunoco card holder for about 5 years now.. i used to constantly use ultra 94 on my turbo hondas, and realized that for the extra X amount of dollars, i should just slap in some octane boost instead. my cars ran fine on 93, and i felt no difference using 94.
sunoco 100 on the otherhand is a totally different story =)

Prior to modern electronic engine management putting "high-test" gas in a car that was not designed to require it (i.e. one with a high compression engine) was a waste of money. An "old wives tale" persisted that high octane gas was somehow more powerful, and much ink has been spilled by automotive scribes over the decades attempting to convince the great unwashed masses (and probably a bunch of washed ones, too) that this wasn't true. The placebo effect was unbeatable, though, and most folks would solemnly assure you that their car had more power if they used high-octane gas.

I'm no mechanical engineer, but I believe that electronic engine management has turned this effect around somewhat. As Brent opined, carmakers can design engines for 91 octane (I belive that's what the sticker on the inside of my new A4's fuel door says), but they can run on 87 octane because engine knock sensors will result in the electronic control unit retarding the timing and therefore reducing power. So, you will get more power out of high test gasoline, even though the engine doesn't ping on "regular".

A one point increase MIGHT be noticeable (sounds doubtful, except on timed track trials), but it might have actually been more than a one point increase if the lower octane gas was from a contaminated batch or one that was marginally over-rated.

dear al, by the way, my car is mtm stage 1 chipped using the 94 sunoco. later, aj

Where do you live, and how do you like the chip?
There's an MTM distributor/installer in Vermont, so I
think after a couple more thousand miles, I'll chip my car.
Give me an idea about how the chip worked for you...any
negative experiences?