4G63 & the APEX

Explanation please :thumbsup:

Venturi effect is sorta like the opposite of ram air effect. When air goes around the vehicle, it creates a higher pressure airmass. When it breaks away from the car (especially at the rear), that portion not in the airstream is regular atmospheric pressure. The regular airmass gets "pulled" toward the passing higher pressure.

If you have a hot engine bay or some sort of cooler that you want to pass air through, this effect will help pull the air through or out of the low pressure area. This idea is widely used on aircraft for exactly this purpose (extracting heat).

Here is a simple test: take a sheet of paper and hold it on the corners of the short side with your thumbs and index fingers. Let the paper drape over normally. Now blow on the bottom, you expect the paper to rise and it does (ram effect). Here's the cool part, blow over the top and the paper will rise too ;) (this is the venturi effect and also how lift works).

Clear as mud???
 
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Some of these guy's may want to use tissue paper for your "test". Otherwise they may spit out a lung. Try it!
 
Faster moving air/fluid exerts a lower pressure. Aircraft wings use this by forcing air above the wing to move faster which creates a pressure difference. The slower moving higher pressure air then pushes the wing up.

The same effect can aslo be seen in the shower. When you have fast moving water it causes a lower pressure inside the shower which pulls the shower curtain inside.
 
As I understood it, the front hood vent pulls radiator heat out, and possibly FMIC if you go that route?

The issue with running a FMIC in a MR configuration is the piping length from the intercooler to the manifold. Subaru puts their intercooler almost directly on top of the manifold to reduce that piping length which allows better throttle response and reduces lag. If one wanted to use a FMIC in a MR car, a water/ air intercooler setup would be better as the compressed air wouldn't need to go a all the way to the front of the car to get cooled and then back in the manifold, only the water cooling the air would need to make that trip. That being said I don't speak from experience on these systems just reporting what I figured... Anyone feel free to correct me..
 
Thanks everyone! Sounds like the different intakes work well together. I really want to be able to drive hard without too many heating issues and am willing to run the necessary i/c - cooler sizes.

So would an intercooler be needed in each of the rear quarter panel intakes or will one be enough?
 
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The issue with running a FMIC in a MR configuration is the piping length from the intercooler to the manifold. Subaru puts their intercooler almost directly on top of the manifold to reduce that piping length which allows better throttle response and reduces lag. If one wanted to use a FMIC in a MR car, a water/ air intercooler setup would be better as the compressed air wouldn't need to go a all the way to the front of the car to get cooled and then back in the manifold, only the water cooling the air would need to make that trip. That being said I don't speak from experience on these systems just reporting what I figured... Anyone feel free to correct me..

I wasn't exactly knowledgable of the reasons an FMIC would be tough in an MR car, it just seemed like a bad idea to me to have piping running all the way to the front of the car and back that has to be airtight the whole way. That's a lot of air moving a long distance. Thanks for explaining.

With air/water, I assume you would then need a separate pump to move the water through?
 
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