when I park in my garage I always open the engine cover to help dissipate the heat.
I started doing this ages ago with jaguar v12. immense amount of heat was generated. maybe not so much w/Porsche but still the issue of perishables suffering heat soak damage is present.


anyone else go to this length?

 

The 997 switches on the fan when too hot in the engine compartment. When the lid is opened, it switches of the fan.

After a good drive it is good to let the engine cool down a bit to get oil temperatures down but there is no need to open the lid on a 997.

 

Opening the hood will allow the heat to escape...but it escapes over the engine. I prefer to let the fan blow air into the engine compartment and out the bottom. Porsche does a lot of climate testing and I'm sure there was a desert in there someplace...and I doubt the engineers opened the hood to cool the engine.

 

All I did "extra" when I first got my Porsche Boxster was to when I parked the car in the garage to turn on a small fan that I had on the floor to blow air at the front and under the car to help circulate air and reduce the amount of heat soak the engine and engine compartment experienced.

Also, I noted that with the car unlocked if the engine compartment heat got too high the engine compartment fan would come on.

'course, with the Boxster there is no easy way to expose the engine which is just as well as opening the engine lid is a poor way to cool the engine.

For my 996 Turbo there is a 2nd fuse that when installed causes the engine compartment fan to run all the time the engine is on. (I do not know if there is something like this with the N/A 997 models.) Also, as per Porsche I let the engine idle a couple of minutes to let the turbos shed some heat before I shut off the engine. But even though the car is parked outside when I'm around it often I hear the engine compartment fan come on.

In the case of your car, leave the engine compartment lid closed and let the engine compartment fan and the logic that turns it on after the engine has been shut off when the engine compartment temperature gets too high do its job.

 

There's always a few guys doing this at the track. It almost seems to make sense, until you think about it and realize the engine is off, its not producing any heat, and whatever tiny little extra bit is dissipated is a teacup in the ocean of heat the engine puts out when driving, running flat out, idling, etc. Oh sure, you feel the heat it seems like you must be doing something. Then you look at a header glowing red hot…. and realize there's a reason its always only a few doing it at the track. (More than a few if Novice day.)

 

I live somewhere that gets up to around 50C (122F) in summer, and I drive a turbo. Never opened the lid for cooling.

 

Actually, once the car is parked and the engine is shut down engine compartment temperatures do spike. Just the movement of the car along the road at speed allows air to circulate the engine compartment and shed heat. Worse, of course, is when the engine is running and you are parked (traffic jam, drive through, etc), engine temps skyrocket and the fan will kick on.

On my daily driver 2004 325i, I routinely pop the hood after parking the car in the garage in summer to dissipate heat. I've done it for years and notice that a lot of the rubber and plastic components are still in nice shape.

My neighbor two doors down has the same car (but a year older). Not long ago, while he had his hood up and working on his car I took a look at his engine and associated parts and pieces. Much of the soft rubber bits were cracked and brittle or just broken. I was actually quite surprised at the difference in our two cars.

Like the Porsche, the BMW radiator/cooling fan may come on after shutting off the engine during hot temps. I believe the activation temperature is on the high side, though. Whatever the case, I've noticed this practice has really paid off on my 200,000 mile BMW. I do it on my Porsche too.

 

....this length....? i hope i would seek professional mental help or swear off crack before i start dealing with ......................issues of perishables suffering heat soak damage is present. on a serious note i will share this beauty of a post at the bar to-day.

 

No, I let the built in fans handle that. Considering I can get the oil temp up close to 225 in the summer here, I don't think the average 200 temp most of the year is hurting anything - it should be able to spend days straight at normal operating temps.

In the Phoenix summer, the fans would run for 5-10 minutes after pretty much every drive. Right now, I barely hear them.

 

Perishables? Not leaving your groceries in the car I hope

The advise I have read is to let the car idle a few minutes before shutting it off after a very hard run when you are still at high operating temps. You can try that if you are concerned but to me that means seeing oil temps over 225 in the driveway. It does come down while running and on occasion the rear fan will trip after you shut it down.

 

Being used to turbos(*), and considering neighborhoods as "no wake zones" (**) I cool down during the last mile or two of my journey.

(*) Don't want to shut off the turbo oil supply when it is spooled up to 60K rpm.

(**) A term borrowed by someone wiser than me on this Forum.

 

Perhaps it may seem a bit overboard to some.

When you own cars that are 20 or 30 years old (or older) you tend to want to try to preserve what you can if possible. For classic car owners some items become "NLA" or No Longer Available. This can mean that certain bits and pieces in the engine compartment, including critical items like fuel lines, may become very difficult to replace. If you've ever had to search for a part and you see the part is NLA, you'll know what I mean.

The day will come when 997s are 20+ years old and the rubber and plastic parts have gotten old and brittle.

If you're the type of owner who picks up a late model 911 (or whatever) drives it for a few years and then moves on - well then who really cares, right..?

 

I completely agree with the above and do the exact same thing. Best way to keep all these plastic hoses and tubes from falling apart due to thermal shocks (e.g. AOS....).

Yves

 

I can't remember what I had for breakfast yesterday (mapo)?
but I do know that I am the type of owner you would want to purchase a car from. I have a lot of mechanical sympathy, and I buy my cars to keep for a long time.
preventive medicine/maintenance is the best medicine/maintenance

 

I agree with most of whats been said here and I typically don't need to let the engine cool at idle as I usually have a mile or two of 'no wake zone' driving before shutting the car off. Occasionally I'll check the oil level and use that time as a little cool down.