ram air intake? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

jhandy · 01-04-2010, 11:22 AM

Just a passing thought...
has anyone ever thought about a ram air intake? I was thinking that the intake tube can be turned downwards and a plastic housing made to pull air from under the car in a true ram air fasion.

I have the EVO intake currently, and it is ok execpt for the housing is prettly lame, and it allows the hot engine air to come in.
There has to be someone out there that has access to CAD and or Plastic molding tech that can custom make a housing that can house the cone filter and ram air in from the bottom, making it a true cold air intake.

Jaxonalden · 01-04-2010, 12:15 PM

You can seal the lame housing by simply adding a thicker seal along the housing edge where you think the air is coming in…it’s that simple. Can’t find where the air is coming in? Remove the access panel behind the seats and reach up inside the engine compartment and feel where the gaps are and seal them. What a true ram air intake? Extend the tube of your EVO so your filter is hanging out the intake opening behind your door, now you’ll really be drawing some air. :dance:

stephen wilson · 01-04-2010, 12:56 PM

Drawing air from under the car has several problems, you won't find a high pressure area of undisturbed air that matches the OEM location (there's not enough ground clearance to add a "scoop"), and the air under the car will be hot from the road surface, and probably from the front radiators.

blue2000s · 01-04-2010, 12:59 PM

Porsche gave us all "true cold air intake"(s) stock.

jhandy · 01-04-2010, 01:27 PM

What I mean by a ram air intake is when you are driving 60 MPH, the air is forced into the filter housing causing a pressure increase via a venturi effect. like a very mini supercharger or weber carb venturi tubes. What porsche gave us was a cold air intake. Restrictive as it was, I have made the biggest mistake ever by putting the EVO intake on my car. The houseing is horriable and the filters cost 79$ each.

The only reason I do not go back to the OEM, is that I love the sound, I do feel that there is a power gain, and the biggest reason is the fact that putting it on was such a PIA, I will not do it again.

Steve Tinker · 01-04-2010, 01:46 PM

If you are familiar with the motorcycle world, you will know that most sports bikes utilise the so called "ram air" system - so much so that even the frames have huge cavities cast in them for the air ducts and in many cases the airboxes are actually larger than the fuel tanks.......
After all is said & done, the manufacturers are loath to quote ram air HP gains, but many dyno results show that you have to be travelling in exess of 120mph to get a significant airbox pressure gain that increases performance.

Of course you could fabricate a huge scoop over the Boxster's air vent which would give you some cooler air, but you would always be pulling out dead animals, birds and handbags from your air filter.
Wouldn't look too good either, but that's subjective. Californians would probably like it....

stephen wilson · 01-04-2010, 02:55 PM

I know that's what you meant by ram air, though much of the gains are from the cooler air temperature. The OEM location will give some ram air effect, it should be in a high pressure zone ahead of the wheel arch bulge. The cowl or front of the car are probably higher pressure areas, but obviously difficult to duct to! An effective ram air intake doesn't have to have a big honkin' scoop to be effective, and the drag from a large scoop may offset any HP gain. Their effectivness is difficult to judge without wind tunnel testing, CFD, or lots of trial an error.

Lobo1186 · 01-04-2010, 07:42 PM

there are scoops you can get for the intake.

http://www.kokeln.com/ram_air_ducts.php

Kirk has them also

Lobo1186 · 01-04-2010, 07:54 PM

Keep in mind that a "cold air intake" does not need to be near the ground. It just so happens that in 95% of cars its the easiest place. all a cold air is, is just getting fresh air from the outside of the car. So our side intake is a Cold air. like blue2000s said. Also unless your motor isnt getting enough air. then ram air wont do a whole lot for you. Its been debated on Mustang and muscle car forums for a long time.

I have seen talk about some owners who have larger motors and say that the location of the intake on the box doesnt give the motor (ITHO) enough air. Im not sure if that is true or not but some went for scoops and some relocated. but either way the easy way is just the scoops relocating wont be easy and you run the risk of ending with a subpar system if not done right.