Mark in Baltimore

I'm pretty thin and couldn't imagine taking the undertray off without jacking the car up. Of course, my car was lowered and had PSS-9's at the time. Maybe the stock ride height is like wiggling through a house's crawl space.

kkim

Uhh... Marc, just too much information in that one line.

JohnJL

Think "spelunking."

Tour18

Ruf has a CTR2 Sport on the floor in Dallas. For $260,000 you get no 'undertray'.

k00k

I've just read in "Original Porsche 911" by Peter Morgan, that the tray supposedly helped with aerodynamics. Any truth in that? I imagine it would have a pretty minimal effect. Personally I'd rather have the cooling benefit here where I live. It was a rather pleasant 40degC or 104F the other day, and summer doesn't really kick in for another month or so...

Edit: How long does it take for my Rennlist Member sig to kick in?

cheers
Mal

BobbyT

Hi Mal,

Leave the tray off.

I was in your beautiful state of Western Australia in the early 60s--an American Marine assigned to the RAAF at Pearce--drink a Swan Lager for me!

Mark in Baltimore

The Cup and GT2 cars never ran with them. Since their engines required frequent rebuilds, you'd figure they would sacrifice the motors in the quest for speed thropugh better aerodynamics.

I've read here that the tray was primarily for noise suppression, not aerodyamnics, in strict countries such as Switzerland.

k00k

Bobby, yep RAAF Pearce base is still there. Just being upgraded at the moment I think. Only about 30 years overdue. And yep, Swan Lager is still going strong. Probably be having a few tonight actually! Yet another party to go to!

Mark, yes he mentions noise suppression as well. Well, I'll be damned if I'll be wanting to suppress that lovely mechanical noise. Thats part of the great attraction for me. I just love the noise these cars make! When I see one that is. Rare as rocking horse **** here in Perth. I actually cant remember seeing a 993 for sale for months here in Perth. My hunt begins in earnest very soon. I'll have to look Australia wide. When I find one, that tray will be going straight into storage...

cheers
Mal

PBenz

From one FL resident to another - my tray is off at all times.

orcfromthesouth

Anyone tried either perforating or opening a slat in the area of the tray directly under the cyl fins?

Orc

mborkow

i did a search on engine tray (limited to the 993 forum) and while there are a quite a few threads they seem to indicate that this was more an issue with the 964 than the 993. i took at a look at my tray last night and i can see some scrapes on it so i am wondering if i had removed the tray if those scrapes would have caused real injury (rather than just flesh wounds to the tray). i drive on HW 101 here in NoCal and there is a ton of debris on the road. just last week a 2x4 bounced under my car and i heard it slam around under there and when i pulled over to have a look underneath i was thanking my lucky stars for the tranny and engine trays. if the tray were only to reduce noise i would say yank it off for sure, but i can't help but think that they engine tray saved me last week.

Mark in Baltimore

Did you check any of Steve Weiner's posts? Good enough for Steve, good enough for me.

If it makes you feel better, leave it on. The chances that I'm going to run over something are much slimmer than the possibility of overheating our air/oil cooled engines.

mborkow

yes, i read steve weiner's posts, but i do not agree that what is good for steve is good for me. here is why i say that. i am a software engineer and am perfectly comfortable fixing my own computers. if a hard drive fails i can replace it, if a cpu fries i can replace it, if my nic stops working i can replace it, etc. i do not buy warranties on my computers and i do not buy from dell...but when my family asks where they should get computers i always send them to dell. i do not do this because i think dell makes a good product (they don't); i do it because for the novice computer user dell is good choice. they have pretty good warranty plans and they will come fix your computer when it breaks. i consider myself a novice porsche owner. i love driving it, but i am not a gearhead. i do not do my own oil changes if something fails on my car i go to a mechanic (and pay through the nose) to get it fixed. so, what may be a good risk for steve with a porsche (or for me with a computer) might not be such a good risk from a novice (like myself with a porsche or my family members with their computers). i have no doubt that steve is correct (he is the expert) but i feel more threatened by the chance of running over a 2x4 then i do at the prospect of *maybe* needing a valve job (after all these cars seem to need those every 70k miles due to the CEL/SAI issue anyway).

i did notice that some people had tried to mod their engine tray by cutting/drilling holes in it so as to offer both better cooling while still protecting the engine. that idea seems interesting. if anyone has had this done and is happy with the results i would be interested to hearing what they think.

Chris W. - '96 Targa

I know the general consensus is to leave the tray off, but just for the sake of discussion (since I don't have a strong opinion on the subject):

If your 993 doesn't ever run hot (per the oil temp gauge), why bother trying to make it run cooler?

Sure, engines in general (air or water cooled) can make more power when cooler -- to an extent. By the same token, the engine needs to be above a certain temperature to function optimally, too.

Any thoughts on how running the engine below "normal" operating temps (i.e., with the engine tray as factory equipped) might *increase* the likelihood of carbon buildup, etc.?

As I recall, part of the "preventative maintenance" for the dreaded carbon buildup problem in the OBD-II cars was to drive the car for lengths of time at higher speeds so the engine would burn off the carbon deposits. If you intentionally cause the engine to run cooler all the time, couldn't you potentially accelerate the carbon buildup?

FWIW, I've kept my engine tray on, mostly because I don't want to have it propped up in a corner of my garage. With just under 60k miles now, I've had no CEL issues or overheating, even in the Florida summer.

Just some random thoughts...



-Chris

993RS

This seems to be a neverending story.

Tray is on for aerodynamics: Why is it that none of the racing versions have a tray on?

Tray is there to protect the engine: The 911 for most of its life time never came with a tray.

Tray is there for noise suppression: Yes, am sure this is the main reason.

My tray is off and stays off. If you need a placebo in thinking your engine is more protected, then keep it on...