Octane

[comptiger5000]

As was said above, unless the engine can take advantage of the extra octane in its ECU tuning, you're just wasting money by going above what the manual says.

My Jeep gets premium (93 both here and at home), as it has a fairly aggressive timing curve, and no knock sensors. The manual requires (not recommends) 91 minimum, and it would definitely ping on any less.

[Creeper]

Originally Posted by Daox

Got any evidence to back that up? I've heard many claim this but have never seen any testing done to back it up.

I'd agree with Patrick that its a waste and is useless unless the engine is programmed to take advantage of it.

Physical proof no but I did help with allot of the Servicing on the van. At 250,000Km the motor started acting up and the economy went through the floor we switched to high octane and the motor stopped acting up and the economy went up a bit. It was not the greatest but hey its an Astro.

As for the post if your motor is tuned for it then go for it. If not don't bother.

[Danncomm]

I have been using octane booster in my gas now for about 3 weeks, the bottle says one ounce boosts normal gas to 108 octane. I have been putting about 3 ounces per 8 gallon fill which boosts to roughly 92-94. It doesnt seem to do much for my normal burning but when I get into lean burn it seems to help boost power. I am able to drive at faster speeds and at the same time keep the higher mileage I was getting running slower. I figure it is costing me about 8 cents per gallon which is cheaper than running the premium gas.

[gone-ot]

Originally Posted by Danncomm

I figure it is costing me about 8 cents per gallon which is cheaper than running the premium gas.

...then, it certainly seems to be "worth it" to you.

...some people gain, some lose and others see nothing.

...wonder if this works for all Prius engines, or only the '06 year model?

[Danncomm]

I would think it would work well in any engine that has a lean burn mode, I don't know who made lean burn mode engines except honda. This would be a cheaper way also for cars that do need higher octane fuels, because they would be able to use the cheaper and more energy dense lower octane fuels and then add the booster. Might not help much maybe a mile or 3 because of the increased energy density of the lower octane fuels and the ability to have the engine advance the ignition slightly and gain from the enhanced burn. Maybe I am full of hot air and misinformation, but this is how it was explained to me. It seems to help with retaining power while in lean burn.