Detonation (Knocking)

[vought]

Hello all - thanks for your help with the speaker install a few months ago.

I'm wondering what octanes and tempertures forum embers are running. Last summer, I drove up a steep hill (CA 17 from Los Gatos to the summit; 1600 foot elevation gain in five miles) on a hot day (109 degrees at 1100 feet!).

I noticed the temp gauge rising to a point near the 3/4 mark of my P10 and dutifully turned my heater on after opening the windows to relieve some heat. Then I noticed some knocking. Yikes!

I've always been told that detonation is the bane of any engine. In my case, I slowed down and let others pass while I neared the summit. I use Plus grade (89 octane) fuel from Shell - the same the car has had since 1996 when it was purchased.

Should have my timing checked at the beginning of what seems like another hot summer? I have to climb over 1900 feet total in the car every day, and 93 octane here in CA is very expensive - I use a tank/week.

My only mod is a K&N filter. Not much of a mod, I know....but at 150k miles, you don't want to mess with (near) perfection.