Not sure what it's called. The stamped aluminum sheet under the engine on my DB9. I remove it for service and reinstall it. I do my oil change and leave it off to make sure there are no leaks. After a hundred miles or so with no leaks I lift the car back up and reinstall it. Is this a protective piece? Is it aerodynamic and come into play to provide downforce at 150+ mph? It's a cool looking piece of stamped aluminum. What is the down side of leaving it off the car? Just wondering. I'll be reinstalling it this weekend. Curious minds want to know.....

 

IME, most modern cars undersides are protected from the elements with some sort of undertray. for the sports car enthusiast, i suspect manufacturers are pandering to the race car wannabes among us. but from a practical POV, it's been written that it is designed to enhance air flow through the radiator(s), cuts down on road noise and improves aerodynamics. to check out that bit of info, it should be simple enough to watch your temp gauge and see if it makes a difference or not. in any event i had mine off a number of times and replaced it every time without too much delay. and i'm pretty lazy, so it crossed my mind to NOT replace it, but i did.
BTW, i once had a vantage pre-purchase exam done on a car in atlanta (i was in california at the time) and they reported that the car didn't even have the engine undertray on it, although i have no doubt one was on it when sold. so if you left it off, you wouldn't be the first. so there's that...

 

It also provides torsional stiffness. Helps keep the car from twisting when cornering.

 

do you have any facts or data to back this up?

IMO the aluminum is too thin for anything other than keeping it's own rigidity at 150+ mph air flow under the car...

 

One thing it will do is break off the bottom of your radiator support if you hit the curb with your front bumper. I learned that the hard way.

 

My bad. I was thinking of the sheer panel.

 

No it doesn’t. It is a thin, wobbly piece of sheet metal. The much thicker plate that covers the cats and spans the torque tube tunnel is a stiffener, and raising the car by one corner with the plate removed is warned against.

 

don't worry about it... i didn't believe you anyway (ha), but didn't make a point of it inasmuch as i didn't think it was that important. anyway, i'll use this little interchange as an example to an ex-wife or two, that have unjustly labeled me hyper-critical, that i'm nothing of the sort.

 

With it installed?

 

Aerodynamics. If you get above 100 you should feel a difference with and and without.