I'm putting only 87gas in my LS right now and I'm never gonna put anything higher. I personally firmly believe that higher octane doesn't affect anything, and if it does, it's too little for me to notice. I run 87 only on my fuel injected Suzuki GSXR sportbike, this engine is definitely more finicky and tells you if your oil sucks/filters are bad/(cant think of any more little parts off the top of my head right now) and it doesn't make a single hiccup or ping (I HAVE had pings before, when the bike was brand new, I actually could feel it with the engine under me) as i string it out at 10-14,000 rpm on the freeway and empty straightaways. My bike eats it up just fine, my lower-tech (yes yes, it IS an advanced engine compared to most other cars, but it's not as high-tolerance and super-fine tuned like a race engine) Lexus will do just as well. Just my 2 cents.