engine knocking when accelerating

[churp]

Originally Posted by swng

This is just for information and reference (please refer to Post #3849 thereof):
http://townhall-talk.edmunds.com/Web...her%20altitude
I can't judge the validity of all the comments.

Edit: Here is another link:
http://www.bp.com/liveassets/bp_inte..._car_knock.pdf
Middle of Page 2 thereof is relevant.

Thanks for the reply....I agree with these links, which basically say the thinner air at high altitudes gives the same effect as lowering the compression ratio (which also means less power) in your engine. I wouldn't use 85 octane even in my ex wifes car though.