is it cool to put 89 octane in a '00 si?

 

i wouldn't and i don't put it in mine.

 

thats what my sister uses in hers..guess its ok, well for her atleast.

 

maybe if you are gonna drive like grandma. why buy a motor with kinda high c/r, decide to fix it up performance wise and then put "el cheapo" gas in it.

 

If you haven't changed heads/cam/ignition timing, use the suggested octane from your owners manual (if you use higher octane you are just wasting money). If you have changed any of those things, use 91+.

 

you don't have to run high test, but it does say premium fuel only for the si.

 

the B16 motor requires the high octane; either you fork out the extra dollars now or more later when you mess something up nasty

 

read the manual. my wife used 87 octane in my SE and we found out the hard way. Did'nt break anything but it was a bitch to get her started again. I was adding octane booster like mofo. I honestly never thought it made that much of a difference in a N/A car but I was wrong.

 

I only use 93 octane