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<x-charset iso-8859-1>Hey Brian- > Is the airflow under the car a low pressure area or high pressure > area? High pressure. That's why your car lifts up at high speeds. > When I switch to DCNFs (hopefully before INVASION), Why DCNFs? You'll learn to hate curves if you get them. The float bowls are not positioned correctly. Trust me... BTDT... > I want to make my > own air cleaners with ducting to a different area than the rear > valance. I was thinking of ducting to each side of the transaxle. The air under there is hot, dirty, and turbulent. I wouldn't choose that option. > Or > would it be better to duct each carb to its respective rear fender > plenum under the louvers? That'd work! Just keep one thing in mind: you have to make the air take a difficult-enough path before the intake so that rain water drops out. > The fan pulls (according to specs I've seen) about 1400cfm, and I > wonder if the carbs and the fan fight for the same air. > It would be nice to find a way to "ram-air" the carbs! Warning: the darkside lurks beyond this sentence; the following paragraph is not for those faint of heart to semi-irreversible body modification... I built a cold-air induction system for my custom FI on my 2615cc T4 engine in my T3 Fastback. I used a ~6.5"x6.5" K&N-style cone filter. I cut a large circle in the rear body ducting to the right of the cooling air inlet. I then did a bit of sheet metal fabrication to hold the filter in there, seal up the cold air intake, and build a ram. I then used some epoxy and some weatherstripping to seal everything up well. The fan sucks a lot of air. So, if you put a tube going straight out of the ducting somewhat near the fan, you'll have a fast airstream moving perpendicular to the tube. Many a venturi device works this way - it's not good for an intake. The worst setup is to "shroud" the intake to the engine to make it draw air from the opposite direction as the flow induced by the fan. This is the stock T3 setup. For my setup, I stuck a sheet metal ram into the chamber to help "force" air coming toward the fan to go into the air cleaner. According to my Autronic computer's data logger, I can make the manifold pressure 98-99% of the atmosphere at any given RPM up through 3rd gear (I haven't hit redline in 4th gear yet... that's about 140mph), so evidently this setup works out pretty well! Also according to the computer, the intake air is nice and cold... nothing like the hot temps in the engine compartment. This whole thing necessitated the removal of the stock T3 oil filler. It doesn't matter much for me because I use a 914-style filler in the breather box, but for you that wouldn't work too well. If you liked this idea, you could do it on the left-hand side instead. Also, if you like the idea of a big cone filter, you can get K&N knockoffs intended for Hondas at Pep Boys for $25. They have an inlet already setup for slipping over a 3" tube. The only problem with them is that they don't come with any filter oil - you have to get that seperately. BTW, the reason I chose the rear side of the ducting and not the sides is that I thought the extra turn in there would help drop out rain water... it rained here recently, and after a long drive I pulled off a piece of the induction system, but it was dry inside. Take care, Shad Laws LN Engineering - Aircooled Precision Performance http://www.LNengineering.com ------------------------------------------------------------------- List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org </x-charset>