I have an '86 TA with the ground effects and I'm having a hard time figuring out if the ground effects are plastic or molded rubber ... or some other material all together. Any help on this would be greatly appreciated.

fg

No, I'm about 99.9% sure it's not fiberglass. Ground effects are a bit too flexible to be fiberglass in my opinion.

Pontiacs use urethane, just like the front and rear bumpers. Camaros use fiberglass.

Very interesting. Is Urethane a porous or non porous material? Another guy just told me that the center section of the ground effect that goes along the door is fiberglass. I've heard that ground effects add quite a bit of weight to the car and I figure that wouldn't be true if they were fiberglass so I still don't think they're fiberglass.