Celtec expanded PVC sheets for aero mods...
 

Just look up this stuff on Amazon, it's pretty cool... Light, heat formable with heat gun, and seems strong enough for aeromod use... Best of all, it presents a more finished look than coroplast, and doesn't cost much more(unless you're getting the coroplast for free)

According to this thread, normal coroplast is 4mm: http://ecomodder.com/forum/showthrea...ets-11862.html

As of right now, Amazon charges $60.16 for a 48" x 96" sheet 4mm thick.

Celtec Expanded PVC Sheet, Satin Smooth Finish, 4mm Thick, 48" Length x 96" Width, White

https://www.youtube.com/watch?v=A-g-TadhMJw

Confirmed, i briefly used it for my wheel skirs and love the stuff. Here they sell it as " foamed PVC" under different brand and claim good UV resistancy. Plus, you can glue it with toluen based glue.

I've been looking for a source of cheap PVC sheet to make wheel skirts. PVC has excellent UV resistance, unlike polypropylene Coroplast. Nice find!

I have a sheet of this stuff I bought last year for a large scale hovercraft model.

Life and business intervened and the sheet sits in my studio untouched.

The sheet I have is rather thin and bends in a nice smooth arc. That arc was to be a main feature of the model.

If you are looking for something stiff go thick, if you want to bend it go thin.

My local plastics shop carries all sorts of plastics, the owner is super friendly and walks me though. I tell him what I'm trying to do often with a sketch and he immediately knows the best product because he also fabricates specialty products in his shop.

I was looking at this material for potential wheel covers the other day...!

But maybe not:
https://en.wikipedia.org/wiki/Closed-cell_PVC_foamboard
If it rubs or burns in any way it can get quite nasty.
Be safe.

The most I've done with the stuff was use a heat gun to bend it, but I imagine it can't be used in the engine bay or near the exhaust.., I mainly plan to use it to fabricate a more permanent lower grille block, once I have the shape worked out so my car won't overheat, and a pair of wheel skirts that look better than the coroplast I used before...