Direct Injection

http://www.theautochannel.com/news/2005/09/25/143868.html

so i understand the concept and all, but how is there no knock?

 

its not that there isnt any possibility for knock, its just reduced due to the fuel having less time to heat up before combustion.

 

the exhaust gasses are int eh chamber also, wouldnt they be hot?

 

yes, but the fuel and air is mixed in the chamber as opposed before the already hot valves, so there is less time for the fuel mixture to heat up.

 

ah