Grounded Knock Sensor (QR25)

Daniel Kort Daniel Kort" <dkort@eng.utoledo.edu
Fri, 26 Jul 2002 18:21:53 -0500


>So I unbolted the knock
>sensor, ziptied it to the firewall, then grounded it to the block.

I have seen a lot of people post about this, but is it really a good idea?
Nissan put it there for a reason, to protect the engine from bad gas, poor
tuning, and different climates.  I do understand that it is over sensitive
and can cause adverse effects to the timing, but how safe is it?  Has anyone
looked at their timing before and after this?  I would be interested to see
how much timing advance you get with it grounded and away from the block
compared to a stock car in the same gear.  In theory, it could advance
beyond what is really safe.

Or is it sensitive enough to still see serious knock when away from the
block and retard timing?

Dan
Old Car www.onelap.com
New Car 02 Spec V