|
I recently acquired this carbon fiber intake plenum for the S14 engine. It was reportedly one of three made
and came from Germany. I am not sure who made it or how long ago it was made, I purchased it used.
This plenum weighs 1.5 lbs. compared to almost 9 lbs. for the stock cast aluminum plenum.
The carbon plenum (or "airbox" as the Germans call it) incorporates all of the standard fittings for
vacuum lines, and for attaching the brake booster hose, the throttle cables, and the support bracket.
|
|
Now a weight reduction of around 8 lbs is not going to make you car any faster, unless
you have already put it on a serious diet (although any weight removed from the front of the
car, and relatively high up is a good thing).
But the nice thing really about this carbon airbox is
that it greatly reduces the mass "hanging" off your throttle body gaskets. It's well known
that the throttle body gaskets on the S14 engine can be prone to vacuum leaks. My personal
belief is that much of this is due to the gaskets getting deformed and tweaked by the
very heavy stock aluminum plenum. As the engine vibrates at high rpm, the small pressed
steel support bracket that is designed to support the plenum will have a tough time keeping it from moving around.
And this
movement of the plenum relative to the engine will cause the throttle body gaskets to suffer.
Another effect of adding this carbon fiber plenum is that it increases the intake
noise from the engine. I happen to think it sounds rather nice, but it was unexpected. Although
in hindsight it makes sense that swapping the thick aluminum plenum for a thin carbon
fiber one would allow more intake noise to leak through.
Since the interface between the carbon fiber plenum and the aluminum airhorns can be a bit tricky
I added a little Loctite adhesive-sealant to make sure that no vacuum leaks would occur down the road.
|
|
This sticker was on the carbon box when I received it. It has something to do with BMW Motorsport.
I do not think that this airbox was made by (or for) BMW Motorsport.
Rasmus from Sweden points out that the sticker is written in Swedish, and that it states that the
plenum complies with Swedish emissions regulations. Another Swede, Andreas, gives a literal translation:
"Information of exhaust control. This vehicle complies with the regulations stated by the National Department of Nature and Environment."
|
Additional Picture #1
of the installed carbon airbox.
|
Additional Picture #2
of the installed carbon airbox.
|
|