Uproar

Hi:

I have been looking for a C-4 and have found what appears to be a excellent example with only 35,000 miles, recent engine reseal and all records. The only detraction I see is that the engine under tray is missing. I am negotiating with the owner to provide a tray. He thinks he has located one, but I'd like to verify the part number. 89 C-4 Coupe, If someone could provide me with the part number I'd be very appreciative. I hope to list soon as a "new owner".

Regards,

Ken Bigham

apw964

Hi Ken,

Mine is a 1990 C4 - Here's the number from my tray
964 119 029 04

Good luck

Andy

Nick Appleton

Ken,when you get your engine undertray, hang it on the garage wall as a piece of modern art and admire.

The general advice seems to be to leave it off to improve cylinder head cooling. I took mine off 12 months ago and have it hung on the wall!

Cheers <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />

rutz964C4

I,ve also heard that it is better to take it off for better cooling, but a mechanic told me to keep it in place to prevent small damages and mud...and also for aerodymamics at high speed on the highways???????

ALEX

Andy Roe

On in Winter to protect from salt etc. Off in Summer to aid cooling!

Tony Davis

I agree with Andy. Its also a very effective drip tray if you have oil leaks. You're call on whether you prefer to catch the oil and hold it near the exhaust or let it escape.

Wsp964

Hi Uproar,

I am kinda confused how a ordinary undertray can make you reluctant to buy a superbe C4, 35.000 miles, all receipts, records, etc ... ??

WSP964

Uproar

Hi WSP:

I'm not reluctant, but I understand that the trays are expensive. I live in Ohio and probably would fall into the off in summer on in winter category. It's just a point of negotiation. Nothing more.

Ken

maverick

The main reason for the undertray was to enable Porsche to comply with stringent Swiss noise emmission standards. Other than that it acts like a sleeping bag to trap hot air around you AIR cooled power plant.
IMHO as to aerodynamics at speed, I would suggest you look at any Porsche Cup Series car and note the LACK of one. If it had any significant aerodynamic benifit they would use them.
Maverick

Adrian

Dear Maverick,
If you ever get to read the Porsche Carrera 4 1989 Service Information manual you might find Porsche have some very different ideas. Track racing and road use are very different things. In the SI manual PAG give an explanation of why the rear cover was used and Swiss noise regulations was certainly part of the process but so was reducing drag.
I am still waiting for the evidence to be presented, even statistically that these covers cause premature wear of anything. Mine has 147, 000 km, engine still as strong as an ox, no oil leaks and the cover has never been removed apart fro servicing purposes. My C4 is driven in all weather and all conditions.
My only caveat is that if you live in a very hot region I would remove it in in summer order to reduce the effect of blowing high external ambient air temperatures over the engine. The M64 engine do run hotter than orignally intended or designed. I also recommend that inspections of the engine cooling baffles are carried out. These are quit critical to engine cooling by directing the airflow to the right places. I also recommend that for high speed driving the cover is installed. Race track cars rarely go fast in a straight line for long. The autobahn is a very different kettle of fish.
Ciao,
Adrian
911C4

maverick

Adrian,
Point well taken. Living in Houston, Texas ambient temperature is an issue. I have driven my cars with and without the tray and have noticed no difference. However on my C2 one benefit from taking it off was I discovered a couple of oil leaks I did not know I had!I guess it comes down to 'fit for purpose'.
Maverick

Uproar

So does anyone have a lead on a used pan.

Ken

91C2wrencher

uproar, I've got a undertray from a 1991 C2, I'd have to check the p/n but it probably the same as the C4 unit, I could be talked into to letting it go....

Uproar

Hi C2 Wrencher:
You can contact me off of the list at Uproar@bright.net with the particulars.

Thanks

Ken Bigham