garrett376

How many factory non-competition cars had them installed?

race911

And how many 2.7L California cars had thermal reactors? Factory has done some weird stuff over the years. Remember suspension think in the late-70's/early-'80's? German guys I ran into when I was getting into these cars were absolutely aghast we would put stiff torsion bars in the still streetable cars. Or large roll bars. Especially roll bars; those guys hated the things.

I trust we're all adults and can make our own decisions. My point of always coming back to the race cars was what I observed in '93 at Daytona. Those Cup Cars didn't have anything but stock bodywork (including the motorized spoiler). None fell off the banking.

But even if it did make a difference, and I ran with and without at whatever track, unless the difference was over one second/lap or so..........the ease of maintenance would prevail for me.

garrett376

just stirring the pot for fun, Ken

pete000

This has to be the all time most talked about topic in the history of Porsche.

Superunknown

On. Helps as a shield against the crap weather, road salt etc... And it catches all the oil drips too...

ianellison

According to the 964 Guru Adrian Streather in his Enthusiasts Companian bottom of page 298

' ...............there is absolutely no evidence, as is discussed elsewhere in this book, that the rear engine cover damages the engine in any way or form. Unless the 964 lives in a very warm and dry environment, it is recommended that this rear cover stay installed. For all Europeans reading this book, leave it on '

Good enough for me!

V

I have one question: Does removing the engine tray mean more dirt/dust etc in the engine compartment? That would be my only concern..

MisterRisky

Possibly... but it also lets oil and dirt out and allows you to clean the engine without all the gunk just ending up on the undertray.

cobalt

It shouldn't the engine compartment is sealed from below. I find that my engine without the cover is perfectly clean. Even after 3k miles of track driving mine stayed clean until my wife plowed the field doing a 1080 spin into dry grass at VIR. Now everything is covered in dirt.

Indycam

A friend run over some junk on the road and it got kicked up . The damage done was surprisingly large .
If he had a tray on , maybe the tray would have taken the impact / protected the expensive bits .

Moral of the story , don't run over crap .

http://www.google.com/search?q=skid+...ient=firefox-a

DLCrow

off - just remember that its basically a powerfull leaf blower and don't park over a pile of dry leaves!

dcbailey

Off

andrew911

I've got my original radio packed in a box. I find a 1970's or even 1980's 911 more appealing with original radio- soon I'll find 1990's more appealing too...as it is, part of me thinks I should have left the old one in. I did use stock speaker sizes so I could switch back and retain the stock look. Sorry I'm off topic on the undertray question

ducnine

I believe that this engine undercover/tray on a 964 is purely for aerodynamics. I have read a few books that have info about the history of the 964 and it seem,from that info, Porsche put this part on to clean up the air under the car. That said I think Adrian Streathers recommends leaving this on in Europe due to the high speeds achieved on autobahn driving for example. As an Aero feature I am thinking the high speed balance of the 964 (non wide bodies) could be effected if the tray is removed. By how much probably only Porsche knows. A 250 bhp 964 achieves the speeds it does due to the aero improvements that it has vs an older 911

The comment about the turbo not having one can be attributed to the fact that the increased power that it makes can overcome some aero deficienies of not having an undercover.

I think living where I live, I will not get close to the limit the 964 is capable of, so I keep the tray off for 2 reasons; 1) make maintanace a heck of a lot easier 2) lets some of that heat escape

I work for an OEM (guesses?) and am involved in aerodynamic development and we have tried undertrays on some of our cars for improved aero benefit (which also could improve fuel economy). We have applied some undertrays to some cars and for others have shown very little benefit versus the cost of the undertray. We develop the cars for the US market where legal speed are not very high so depending on the car some warrant it and some do not. I am not claiming to be an expert in this topic by any means but my opinions are based mainly on my work experiance.

Rich W

I live in a hot, dry climate.

OFF!

But I took it off in a hot, humid climate and threw it in the trash. Hardly worth the effort to move it across the country.