Vented Bonnet (hood)

[POLARBEAR666]

Underbonnet temps will be greatly reduced by having a vent that is parallel to the front of the car and within the first 30-50cm of the bonnet as this is the low pressure area of the bonnet and will encourage the greatest pull through the radiator and intercooler ... As per WRC car vent placement near the front nose on bonnet.

I fitted rear facing scoop on my STI and my water temp struggled to get up to normal operating. With the scoop the normal way around it was always at temp or sizzling the water cap.

 

[Jig]

So educate me pls. How can air enter those vents if it is facing the other way around?

 

[Paul_OH]

So educate me pls. How can air enter those vents if it is facing the other way around?

When a car travels at speed there is a high pressure zone where the bonnet meets the windscreen. High pressure there > lower pressure inside the engine bay = flow into engine bay.
That’s also one of the reasons why cabin ventilation inlets are always just in front of the windscreen.

Paul

 

[zz2]

Go for a DIY job.

speed holes eh?

 

[KWICKS]

Go for a DIY job.

Here's one prepared earlier:

 

[RoamingNick]

Apparently seibon is awefull fittament

Yep, the gaps are all over the place. Messy.

 

[FJ_Steve]

When a car travels at speed there is a high pressure zone where the bonnet meets the windscreen. High pressure there > lower pressure inside the engine bay = flow into engine bay.
That’s also one of the reasons why cabin ventilation inlets are always just in front of the windscreen.

Paul

Go to the front of the class Paul. Take your books, you might be there a while. :thumbup:
Same principle as keeping a 747 in the air. Air flow and airpressure = lift. In this case...the air flow will always be looking for a low pressure area (lower resistance)