Undertray Ducting

[straylight]

I am currently designing an undertray for my Mazda Miata. The tray will be used in conjunction with a new front end and rear diffuser in an effort to generate downforce or, at the very least, look pretty when the car is upside down.

This is more of a pet project than anything. I'm not expecting great results, but I don't want to create any problems, either. My primary concern is transmission cooling. A sealed flat bottom will inevitably result in a cooked gearbox. Seeing as I've already eaten four due to sheer HP, I'm not fond of this idea.

Getting to the point, what sort of ducting should I incorporate to create airflow over the transmission? A NACA duct probably wouldn't provide enough flow to be effective, and all of my other ideas would create too much flow disturbance to make the undertray worthwhile. I would prefer not to install a transmission cooler, but I won't rule it out.

Thanks in advance.

--straylight--

 

[carnage1]

Auto or stick shift?
If a stick (my assumption) there are other possibilities besides cooling that could extend your trans life.
more frequent trans oil changes, different viscosity fluid, or just not driving

If an auto just do yourself a favor and get an extra cooler and a magnafine filter.

 

[straylight]

Stick shift, of course! Who in their right mind would go to this much work for an automatic, ;-). A sequential transmission is in the works, but that is a long ways off unless a sponsor puts up a great deal of the cash.