Bill Eastman <william.eastman@medtronic.com> wrote:
>Subject: Static timing accuracy
>
>One more thing, according to the literature that I have read, light knock
>is not destructive. I ran a Chevy Blazer for years with a light part
>throttle knock with no apparent damage. If I backed off the timing the gas
>mileage went from merely godawful to downright horrendous. I was a
>teenager at the time so my good luck was not due to conservative use of the
>throttle.
>
I can verify this. In the early '80s, I did some work on electronic knock
detection and ignition timing control. We were working with the European
arm of a large US auto manufacturer.
At that time, their engineers wanted to eliminate the light low-speed knock
simply because of the owner complaints they received. Apparently, their
engines produced more power when running under light knock conditions and
no damage was caused.
High speed knock is a different animal altogether. Firstly, it is not
generally audible, secondly, it causes a rapid heat build-up which leads to
rapid engine self-destruction.
Simon
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Simon Matthews Avant! Corporation
Phone: (510) 413-8820
Fax: (510) 413-8080
E-mail: simon_matthews@avanticorp.com
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