why does the turbos need one or two step colder spark plugs. I know avoid detonation... but what does the spark make to avoid detonation??

and what other thing this thing does?

 

It's a coolness thing. I run colder spark plugs so I can be just that much cooler.

Seriously...
The "temp" range of a spark plug has to do with how fast the spark plug sheds heat, not the heat OF the plug itself.

In a N/A engine, the combustion chamber temps are lower than they are in a supercharged motor (nitrous, turbo or supercharger). The added oxygen and fuel that creates the more power, also creates more heat.

If you didn't install a colder spark plug, the spark plug would keep getting hotter and hotter until it became a source for detonation. It just would not be able to shed the eat fast enough.

By moving to a colder spark plug, the spark plug can get rid of that extra heat faster, keeping the combustion chamber cool, and preventing detonation.

 

ohh ok. thanks!. now I know why the colder sparks plugs!.

smile.gif

 

Random, if you increase compression in a NA setup, for example from 10,3:1 to 10,8:1 ~ 11:1 would the heat in chamber increase enough as to need a colder plug also? Or it's not that dramatical in terms of heat in chamber?

 

I was curious of this too, thanks