Rain coming through hood vents?

[free2rhyme]

im thinking of putting some mitsubishi evolution 1-3 style of hood vents. the two middle ones should be above the exhaust/radiator and the third will be above the air box. So will rain cause any problems for the engine? im mostly worried about the intake part because thats really open and heaps will come through. the two center ones wouldn't be to bad especially when driving cause almost nothing would get in because they face back but if rain did come in could it cause the exhaust manifold to crack?