i tried switching from 87 to 91 octane and it made my car run like crap. its less powerful and less responsive. this is the second time i have tried this, from two different brands of gas. my car is a very healthy 89 crx dx. any ideas???
higher octane gas is actually harder to ignite, which is why it works well in high compression motors. the heat from high compression motors will not detonate the air/fuel mixture. what motor are you running?