I bought the ngk spark plugs for 93 rx-7.
the guy work at the shop gave me two leading and two trailing apark plugs.
leading goes to front rotor and trailing goes to rear rotor? what is the difference between leading and trailing? I am just curious.

 

If i remember correctly the leading plugs are the ones closest to the bottom of the motor (closest to the ground) and the trailing are the ones towards the top.

 

so, leading and trailing has a different spark?

 

They spark at different times.
I think that www.rotaryengineillustrated.com can explain it better with its animations than I can text.

Each rotor has a leading and a trailing, not leading rotor is in front, or however you were explaining in your first post.

 

Good link. Very usefull

Thanks ijneb

 

Think of it this way....
Leading spark plugs go on the Lower side of the housings.
Trailing spark plugs go on the Top of the housings.