dapplestein

What is the factory's rationale for under trays on 993's? Are yours on or off? All of them or just one or two? For those who have taken them off, what's been your experience?

ginch

gmorat

I don't want to get into it really too much but when I bought my car the undertray was on the car. My shop here removed it without asking and said it stopped the engine from cooling properly and it hid oil-leaks.

Good enough for me.

gonzilla

Why on earth would you ever take it off? I'm sure the car would be too loud without anything there to muffle the sound! Plus I'm sure the car wouldn't generate enough downforce at speed and simply fly away!!!

lopro

I was just lectured about this a few weeks ago, the guy claimed the car was designed to be at speed an at speed that air makes its way around the engine with the lower covers on just fine. I had my cover off and he told me to put it back on. To be honest I can see how it would trap heat tho

Mike in Chi

Here is the actual story of why they exist:

Way back when, when Rennlist was called Porsche List, the factory liked the on-line community John D was building dedicated to the Marque. They asked John D. how they could help. Our founder, with remarkable insight and understanding into how social media works, asked them to add something useless and potentially controversial to the new 993... Something that could be the genesis of dozens, if not hundreds of discussion threads.

The factory succeeded far beyond John D's wildest dreams.

(This is a true story. It was related to me by JimBob Jumpback a number of years ago.)

goofballdeluxe

This has been discussed a million times.

Many run without one, due to possible (thus far unproven) benefits to cooling.

Many also don't know that one risks damage to components underneath the car if one runs without an engine tray on a car that has been lowered; things such as like heat flapper boxes catching on driveways, etc. Ask me how I know.

H.H.Chinn

As well as Porsche 'N' rated tires, Porsche recommended oil, and Tiptronic transmissions.

User 122821

Off, so I can keep them pristine to sell in the future for retirement funds.

mongrelcat

I took mine off, because Steve said so™.

It is too loud. Which is just right.

The basket-handle on my car more than makes up for the loss of downforce.

ca993twin

The Porsche factory has not specified the reason for the rear undertray (at least from what I've heard). The speculation is that it is there for aerodynamics, or for noise reduction, or to protect some of the low-hanging parts. There is some empirical evidence that leaving it off promotes better cooling, and it is certainly true that it is easier to jack up the rear with the tray removed and its easier to work on the underside and spot oil leaks. Your choice. Mine is off.

TMc993

Did tha' search for ya:

https://rennlist.com/forums/993-foru...964-board.html
https://rennlist.com/forums/993-foru...undertray.html
https://rennlist.com/forums/993-foru...undertray.html
https://rennlist.com/forums/993-foru...yes-again.html

Steve Weiner-Rennsport Systems

Best use I've found for these things; keeps tree debris clear during winter months here in OR:

Pags993

^^ Love it, that about says it all for me too. Removed the piece of crap on day #2 of ownership.

Kika

is that the same reason we have so many best oil threads too?