I always put premium has anyone tried anything less and how does the car feel.

You should put the octane in numbers e.g 94,93,89,87

I got slammed last time I said this. My owner's manual for my 1992 SC400 says to use 91 octane gas.
I Always fill up when I hit 1/2 empty. Therefore I fillup with 93 octane, burn it down to 1/2 empty then fill up with the mid range. (89 octane) Mixed I get: 93 + 89 = 182 / 2 = 91 octane.
I have been doing this for a year. When I am not sure which I filled up with last time, I always go with the 93 octane. So far it is working just great.

i went to midgrade (89 octane) herein denver.
no knocking or any other adverse performance.
if any problem starts to show, i'l immediately go to 91.

i went to midgrade (89 octane) herein denver.
no knocking or any other adverse performance.
if any problem starts to show, i'l immediately go to 91.

Your engine's knock sensor may be able to back the timing off before you notice knock, and if you don't really push on it, you may not notice it anyway.

I got slammed last time I said this. My owner's manual for my 1992 SC400 says to use 91 octane gas.
I Always fill up when I hit 1/2 empty. Therefore I fillup with 93 octane, burn it down to 1/2 empty then fill up with the mid range. (89 octane) Mixed I get: 93 + 89 = 182 / 2 = 91 octane.
I have been doing this for a year. When I am not sure which I filled up with last time, I always go with the 93 octane. So far it is working just great.

It probably works just fine. At any given point in time your gas octane will be between 90 and 92, and will oscillate up and down each tankful.

I use Chevron regular unleaded for my ES 300 and the Chevron premium for my GS 300 and SC400.

shells v power baby! :D

87. More is a waste for us. When I need to run higher octane I don't.
That's what water injection is for.


Water > Octane

87. More is a waste for us. When I need to run higher octane I don't.
That's what water injection is for.


Water > Octane

The average person will not use water injection in their vehicles nor would they need to. 87 is perfectly fine for the old school 3VZ-FE as it's not a very high compression motor to begin with compared to newer Lexus engines.

midrange 89 3 out of 4 times and then that 1 out of 4 is 93 octane on my Rx300