tabasco

On the PCA tech forums in december, Joel Reiser recommended to disconnect the clutch vent.

The main reason for this is that the vent brings dirty clutch particles right into the air filter. Doesn't help to keep it clean !

Other potential advantages :
I think it would make it easier to change the spark plugs if the tube goes away.
It would save some weight.
The depression under the car (at speed) would suck the particles away, so do we really need this thing being connected to the air filter ?

The race cars don't have that vent.

So it sounds like a pretty good idea to do it, and let that vent join the engine tray in the attic. Has anyone done it ? Is there any good way to do it ?

Or is it a bad idea ?

-Guillaume

JM993

I did it a long time ago (approximate 30K miles). No problems whatsoever.

To clean things up further, I actually replaced the engine tin with a solid piece (no hole) from a tiptronic car.

Frankly, I see no need to "pollute" my intake tract.

FLYT993

Interesting. Since it is an OEM design, there has to be some reason WHY the factory designed it that way?

Garth S

I removed the tube as well; however, a short (~6") angled tube was attached at the bell housing to keep debris from finding its way into the clutch - and to blast the black clutch dust to atmosphere ( along with my brake dust ). Also, a sheet metal plate was easily cut out and screwed to the engine tin via the tube mounting holes.

Garth S

Add (quasi)plausible reasons;
1) didn't want to get the engine tray dirty with clutch dust ..
2) pilot dust collection system for base models - the planned enviro "Green" option was to duct in 4 more tubes from the brake calipers ..
3) to give a "visual" indicator of when to change the air filter - as they otherwise rarely look dirty at the recommended change interval ...
4) ___________ ....

AOW162435

Interesting. Did you leave the port on the transmission housing open? Is there a Tiptronic-specific airbox cover?

Andreas

Marlon

Original design might have been part of the Porsche 'green' effort as it relates to car design vis-a-vis noise and air pollution. The 993 was to represent a nirvana of low noise and atmosperic pollution. Since, for some reason, the tranny needed to be vented, they chose to vent it a-la a PCV system, in effect, making it a closed system. By removing the vent tube, the system is now open to the atmosphere and contributing to yukky pollution and perhaps contamination of the tranny. Not sure what performance enhancement is to be gained from this proposed mod. The vent tube only weighs a few ounces and the plug changing ritual is not such a frequently occuring ritual on a street-only car to justify the mod in my mind. This is strictly a 02Cts worth input.

BTW: AFter I changed all my plugs a couple months ago, I could not get the flexible vent hose reconnected to the rigid pipe because the hose was pretty beat up and I really need three hands to do it, so in effect I am polluting

Bull

I took it off both of my 993s, as I want all the "clean" air I can get going into the filter and engine. BTW, there was no increase in dust/dirt in the engine compartment.

tabasco

No it's not a performance mod. I was kidding with the weight thing. The main goal here is to get a clean air filter.
The rest (if any) is just bonus.

Marlon

Air filters literally cost 'pennies' and I have not noticed an unacceptable air filter life issue related to tranny air.

tabasco

The tube idea sounds good. I too would be worried about debris getting into the clutch.
Do you have pictures of that tube ? Where did you source it ?

Garth S

Sorry - no pics taken: quite simple really, just hacksawed a piece from the old tube and attached it as a rearward mounted down spout. The tinwork cover was zipped from a piece of sheet with tinsnips.

Robin 993DX

Why bother, if you leave it off then you have more opening for air to enter just like the Fabspeed air box now!

Robin 993DX

For that same reason I left it as it is.

Garth S

The plate I added was to seal the hole in the air ducting tinwork around the engine ( near #5 cyl) .... not the air cleaner