Is this before or after buing the race gas that is available right there?

 

We go for a good 10 min drive after 30 min sessions. So far so good. I wonder what it will be like at events in Scottsdale/Phoenix (I am moving there). Any input from other aircooled guys who live in the desert?

 

Sure your sarcasm detector wasn't broken that day?

 

Being a newbie, can you tell me if its ok to push the car hard when its really hot outside. I have a stage 3 and the summer is coming in which it gets really hot here in Southern California.

 

I would think the best way of cooling your motor would be pop the lid and have fans underneath, It would be pointless if it's a warm day and the fan is drawing in warm air (lid closed) to try and cool the engine, it sounds like that would be a losing battle. Bascially everyone knows heat rises so get these fans underneath to blow it up through the engine bay.

 

ill let you know tomorrow what the concensus is from any pcar guys who come to firebird...friggin place is heatin up now around the 90s already

Also, during the summer months most track events are early morning and after dark to avoid midday heat

 

The lower part of the engine, not to mention the pavement on a sunny day, is much hotter than the upper part of the engine. Drawing air from under the car would only INCREASE engine temperature. This is not theory, but fact. If drawing air from beneath the car was more efficient, the deck lid fan flow would be reversed.

Talk about inviting heat soak.

 

I totally agree with you!

 

Opening the engine cover might cool it faster. The hot parts create an updraft by heating the air, which rises out the open cover. This chimney effect might move more air than the little engine cover fan. You'd also get additional heat loss by radiation with the cover open.

 

Glad someone agrees!

But you might find someone might have something to say about this!!!

 

Easy to test (which I have done extensively) Hook up your scanner and watch both the engine compartment temp and water temp and oil temp. Openning the deck increases temps MUCH higher before they begin to drop and keeping the deck lid closed with fan running immediately starts to decrease the temps of all 3. Doesn't sound like there is much to debate here...is there? For maximum cooling, the deck fan should be running at all times.

But, again, there are still many that think running Mobil 0W40 is good for the engine while their oil temperature sits at +240F.

 

Anyone know what specifically triggers the deck lid to go on after shutting down?

 

My fan doesn't run until the car sits about 2-3 minutes usually. I don't think the underhood temp sensor can be read with most scanners. I may test it both ways with my infared thermometer after driving home from work this summer.

 

There is an engine compartment temperature sensor that will turn the fan on when the compartment reaches a specific temp (180 approximately) or when you collant temp gets too high. The lid is designed to push air from the top of the engine downward and out the bottom of the car. The fan encourages this movement and will quickly cool the engine compartment.

 

Not to hijack the thread, but to a first approximation, no oil is any
better than another oil at a given temperature, until you define the
sizes of the gaps through which it must flow, and the film thicknesses
it needs to provide, based on the gaps and the smoothness of the
parts etc. If Porsche says their engines need XYZ, you should believe
them. If a Formula-1 engine designer wants a straight 0-weight for
their engine, they're not stupid.
Thickness beyond the mechanical requirements is a penalty. As a
second-order fact, all oils degrade with heat, but thicker oils produce
more heat internally because of fluid friction (viscosity) so they will
degrade quicker in the same engineering environment.
The the degree that oil is a coolant (not just a lubricant) you want
lots of flow, not resistence to flow. No matter whether an oil is thin or
thick if it's not moving sufficiently quickly through the hottest areas
it can burn, causing deposits which damage the engine. Thin flows
faster at less pressure. So, for a given engine, at an operating temp-
erature of 240+ degrees, for instance, 0-40 might be *just what the
doctor ordered*, and any thinner or thicker might be slightly riskier
for the one reason or the other.
I'm sure we all know this, but as I've said in the past, unless you
can bear a ridiculous conspiracy theory about Porsche's ulterior
motives, no one has the credibility to second guess Porsche on this
topic, in my opinion.
Joe