I'm finally boosted and running A/C as well, so i'm looking to drop my under the hood temps a lot so the A/C actually blows a little colder than it is.. I realize the temps will never drop as low as it was without boost, but my idea is to cut a portion of the hood like mitsubishi did for the EVO..

my main concern is rain hitting the turbine/CHRA and causing cracks when it's at full temp.. somewhat like an ice cube being cooled down too quickly, or a piece of glass..

I thought about venting a little furthur back, but the fact that heat rises makes me really want to go with the EVO location, and i'd hate for water to build up on top of my engine all the time, possibly making it's way into my spark plug holes or something of that nature.. what do you guys think??

right now my ECT sits between 195 and 200 *F, so it's not actually overheating...

 

search hybridcivic lst or look for his post he is a mod here he had a really good thread about underhood temps and he even did something like this i think you would be fine doing it what kinda setup do you have like manifold ?

 

https://honda-tech.com/zerothread?id=2370133

i just order a VIS evo hood for this reason. car isnt driven in the rain and im too lazy to cut my own vents

 

So now there are 3 of these threads..
Yes, it works. The vent in the front part of the hood creates a low pressure area and pulls air out at speed, (but farther back is not a low pressure area, the rear of the hood is a high pressure area, that's how cowl induction works) and it lets hot air out by convection when the car is sitting. It is an excellent mod to do.
Rain won't crack the hot turbine housing. I can tell you this from personal experience. Maybe if you poured a gallon of water on it or something, but sitting at stoplights in the rain will just make a little steam, if you have the vent right over the turbo. At speed, the rain won't be able to fall through.