just anicdotal, but I get better mileage and performance with premium, than ethenol blend

and I ave found that I get better mileage on regular than premium. I have found I get the worst mileage on the ethanol blended fuel, I only tried it a couple times.

All pump gasolines have essentially the same energy, it's the alcohol that has less. Premium shouldn't yield better mileage, or performance for that matter, in fact the reverse should be true. All engines and conditions are different and if the engine is knock senstive, a higher octane may help. I don't know where you live but the best gas I could buy in Kansas was only 91 octane, close to what we have as mid-grade here. I had to be very careful on that stuff as the turbo. engine was very knock prone with it.

WTF?

all of our regular gas is 10% ethenol

I should have qualified that. On an engine tuned for 87 octane, premium offers no advantage over regular. Unless the timing is advanced to take advantage of the higher knock threshold of premium, the power output should actually be less, ar at least less responsive. I also said all engines are different and if high miles has created a lot of buildup, or maybe a hot spot in the chamber, premium fuel can help. For best output the engine should run close to the edge of knock, not beyond it, but close. Moving the knock point further away from the threshold, without adding timing or pressure to bring it back close to the edge, should not increase performance. It may feel smoother due to a more controlled (I can't say slower) burn. I experimented years ago between 87 and 93 octane in my stock engine and chip. It always "felt" snappier and would spin the tires more on 87 octane. Not an exact test of course, and conditions constantly change, but this switching back and forth went on for more than a month and several tanks of fuel. Some blending occurs out of necessity, but those were my results. The other thing I noticed was it started better on regular. It's easy to try different fuels and find what works best for you.

Sc here.. i know for fact that i run like shit on 89... in all standpoints

Uhh, yeah, pressure makes all the difference. :oops: Mine won't run well on that either. The statement about 87 and an N/A engine tuned for it is valid.

that has been the general consensus of the club

Well my car is NEVER going to get premium gas in it, or mid-grade for that matter. It is a beater and always will be so any way i can find to pinch pennies is worth it. The reason E85 is so much cheaper here is because we grow a LOT of corn, so it's really easy to cut down our gas usage. What i really should do is buy a diesel but i kind of... u know hate them. I have a friend whos dad just bought one to convert to vegetable oil though. Kind of a neat idea.