Hello, I like air to air, but you must get enough air
. Because you have transplanted the WRX enging into a bug, has caused some varibles to be address. Wally has air, a must. I don't know the CFM of your fans, and then the size of you intercooler is of concern also. lastly the plumbing wow
the right side is in conflict with the left side. I feel that you attempt to keep it under the the hood is going to give you a temp problem. How about some reverse louvers and add some water injection to it also. You have got to get some non-engine air through the intercooler. water injection is a way to go as a addition. Tilting the engine deck lid will act as a scoop.
http://www.spoolinperformance.com/pr...g-c-52_65.html
you may need to chop up that intercooler to meet you needs.
http://www.vecco.com/products.php?sub_cat_id=13
http://www.alcoholinjectionsystems.c...duct_info.html
This company makes some collector that will work on you project and help correct that plumbing gridlock.
http://www.spdexhaust.com/CollectorsB.html#
Even water has it issues, more plumbing, and where is it going to be located? Up front with the reaiator? Alot of piping. I think air to is should win.