Why do people raise their engine hoods - looks/heat/both?

hey tim..do you have any sound clips of the capristo? i would love to hear it

 

Well,I own a 308. And,even though it has those big Louvers over the Engine compartment,it still gets really Hot in there.

I suppose that when I go to a Ferrari,or other Car Show,it's for both reasons. My engine compartment is very clean,so,I like to Show it off a little.

But,after I've been driving it alot,and just park in my Garage,I usually open it up to let the Heat escape quicker. Probably no need or real reason to,but,I just do....

 

Not really problems, just to aid in letting the heat out so that it goes quicker. Don't really think there are any inherent issues regarding heat displacement though. Did learn from my buddy 512Proffesore the detailer that letting the engine heat sit idle in the compartment can heat and possibly neutralize the wax on that area of the decklid. Just food for thought.

 

Ditto, I am thinking about capristo vs tubi for my car! Any clips?

 

I always open the hood primarily to get rid of all that heat! its a habit with me.

 

Thanks a lot Tim, I appreciate it.

 

I've seen a Testarossa hot enough to melt the tail lights!

But I believe it had a cat issue needing attention.

 

I should say it has a heat problem!

 

The general reason for lifting the engine bonnet is to release the heat. Your hoses, gaskets, and rubber parts will generally last longer if they are not subjected to those levels of heat.

When I have backed my F-car into the garage, I open my door and immediately pop the engine bonnet. It's almost automatic now.

 

As stated above, I also pop the bonnet to let the heat escape. In the summer, it can get really hot in the engine compartment of a spider..........and with that glass back there.......if the sun is directly on it, it is like a magnifying glass. You could cook on that engine!

 

I used to do it for heat reasons, but then I figured it was goofy. Perhaps I should start doing it again on the 308 as well as my Saturn and M3? Nah. Still goofy.

 

Good points about the hoses and rubber, never thought of that. It is also an automatic with me as well.

 

When the car is moving there is usually airflow through the compartment. When stopped the temps go through the roof, no air flow and no circulating water either.

It makes rubber and plastic deteriorate quickly. Causes cracking of electrical insulation. It can also boil the gas in the carburetors (on a carbed car) and/or cause vapor lock in a fuel lines.

Opening the hatch also reduces the amount of 'green pee' that emenates from the rear of my 308 on occasion.

DJ

 

I wouldn't say no airflow. Free convection man! But while there is little airflow compared to driving at speed, there's no more heat generation since the engine has been shut down.

So why not do this on your daily driver? Most daily drivers have more restricted heat vents compared to Ferraris (no open grills on the decks), and those plastics and rubbers last a LONG time.

 

Yes, there is convection and no it doesn't compare to driving speed so why not enhance the convection by opening the hatch?

There may be no CONTINUING heat generation after shut down but there is still an engine in the bay at full operating tempurature that suddenly has little ventilation and NO coolant circulation. The absence of these two cooling agents allow the tempurature to RISE ABOVE NORMAL.

In answer to the question of why I don't do this to my daily drivers?

Neither have all aluminum engines shoe horned into the middle of the car. The bottom of both are wide open and the front end is open on both. It still gets hot as hell under there though but at least the ancillary systems are one heck of a lot cheaper and easier to replace than on the 308.

Vapor locks have been known to occur on 240Z's quite often. Mine doesn't because the fuel lines are covered in braided aluminum. Gas also boils in the carbs because they are right over the header. So maybe I should start opening the hood on that as well.

Note; The wiring under the hood of both of my daily drivers have had cracked insulation and cooked hoses from the heat which reinforces my point.

DJ

 

When the engine is stopped the cooling system slows, opening the bonnet helps cooling.

 

Same here on a 308

 

I never opened my hood...