Slang Time

what is the definition of your turbo car to be knocking?

Knocking is just another word for "preignition" or "detonation". To put it short and sweet, it's when there is too much heat in the combustion chamber (generally caused by a lean A/F, or too-low octane), and the fuel/air mixture ignites causing small explosions around the chamber before it is supposed to- which is when the piston reaches near top-dead center and the spark plug fires. Too much knock can cause severe damage to the engine internals! To sum it up, knock = bad.

I'll let someone else get more in-depth if they feel like it ;)


EDIT >>> I just found this article on detonation/preignition/knock. It's VERY in-depth as it explains the actual differences between preignition and detonation. :) http://www.streetrodstuff.com/Articles/Engine/Detonation/index.php

Knocking is a sound, and it happens either from detonation or a broken part, like a rod. Knocking in terms of tuning is covered extensively. Search around.

here it is straight from the FAQ thread stickied at the top of the forum. lets do a little research before we post.;) next here is kevin spreading his knowledge all over this board. :thumbsup:

http://www.automotiveforums.com/vbulletin/showthread.php?t=164870