Marlon

One other thing to consider possibly: The 'stock' lid is designed (by accident or on purpose) so that when it rains, water coming thru the spoiler grill cannot soak your filter. With the extreme-cut out lid rain water will soak your filter and could make it breath LESS than a dry filter. Of course if you are pulling enough vacum it may be moot. But the engine pulls the most vacum at idle and pulls most aire volume at WOT. So for all you engineers out there - how does a water logged 993 paper filter increase, decrease or no affect on 993 performance?

Also: even though it is (probably) true that the throttle body will see more air volume with a cut out lid - there is no 'directed' dwell air with a cut out lid. The air coming into the inlet is subject to whatever the wind and air mass movement might be inside the engine compartment for a given moment. On the other hand, with the stock lid, the air is always 'directed' in a one-way movement regardless of the engine operating parameter. You could almost call this a desired 'dynamic dwell' situation??? Thoughts?

jimbo3

WAYYYY too much time on your hands, Marlon. I try not to out-think the Porsche engineers as it hurts my pointy little head.

-Jim

FotoVeloce

I don't get it. Why all this drilling and permanent mods. If you want to add some extra noise and possibly flow (jury out) just remove the stock horn from the airbox. It really opens it up, and it's easy to revert back to stock.

allill

If I won't be able to hear it with the LPMM's I might as well not do it!

DocTock993

The other part of all of this that I do not understand involves opening up the Pandora's Box on the discussion about cooler air and HP.
If you have all these holes in the side of the airbox, with no additional outside air under the decklid, aren't you in effect just bringing more warm air into the combustion chamber?
Personally, with the "trumpet" to my fixed wing bringing in nice cooler air, and the sound of the Supercups, I feel no need to hack up my airbox lid..

Mark in Baltimore

When the car is moving at speed, so much cool air is coming in, it's blowing out the hot air. I have my Moton nitrogen canisters mounted directly above the engine. After a 25 minute race with high ambient temperatures, those cans are very cool. Why? Because the hot air is being evacuated. If I forget to lift the engine lid after a session, the heat from the engine soaks into the cans, thus, getting them quite hot.

ninjabones

Can you post the details of your "trumpet". I have a fixed wing and would be interested to hear about how your rigged the intake.

Pete Lech

I have the trumpet and also have drilled my airbox. It would be interesting to know if the airflow from the tail creates positive pressure in the airbox such that it would not pull in the warmer air from the drilled holes. In any case, the sound at WOT is awesome.

One could tape over the holes, retain most of the sound benefits, and avoid any hot air intake from the engine.

McGarrett

I definitly do not have a lack of cool air coming into the engine bay. The GT2 wing at speed is very effective.

Dan V

Time to Unpimp ze Auto

FisterD

Ye haw!
Glad your still enjoying it, Todd.

hyphenf15

I have that very lid on my car. I like the look and the fit. Gives more room to check and add oil as required to boot. Best of luck on your decision.

Bull

I drove my last 993 for 6 years with an airbox that was cut open like the Fabspeed unit. I never experienced a bit of rain water or wash water getting on the filter element. Has anyone actually found that their filter element gets wet after cutting open an airbox???????

hyphenf15

I haven't noticed any water issues with my current setup. It's been on the car for a year and a half.

Toddimus

I love 'em Darin. Great job!

I have to retract my earlier statement. I did a couple of two-lane road passes this weekend, and I sure could hear the induction roar. Especially when the Varioram opens up. The exhaust is at full roar, but you can hear the cylinders begging for more intake air.

I think I woke up the neighbors, and literally, I mean literally, scared the crap out of my wife. Man these cars are fun to drive!