I saw many CF hood with vent on it....I just wonder what if rain goes in?is it going to damage the engine part?

 

Nope, with the J's Racing hood it just hits the airbox and rolls off to the sides. I've washed my car with the hood on and have had zero issues.

I don't know about the vents on the Mugen.

 

Mugen and Top Secret have rain channels.
J's does not. But it really depends on placement of the vents. Like Elistan says the J's vent is directly over the tightly sealed airbox so not much can get damaged with water.

 

Amuse also has no rain gutter, but the vent is about the same location as the J's hood, so I don't think it will be a problem either.

 

thanx for you guys........