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.

 

It is sorta a mix between plastic and molded rubber. It is rather flexible and can be repaired with plastic epoxy from advanced, i have had luck with fixing a rather large crack with this stuff.

 

Well the reason I'm trying to find out is because I'm buying Zaino polishes and if it's plastic (non porous) then I have to use Z-14 but if it's Molded Rubber then it's porous and I'll have to use Z-16. One guy said it was fiberglass but I'm pretty sure they're not FG.

Also, is the front bumper on the TAs made of the same material as the ground effects, it sure seems like it is.

 

The center sections that cover the door area and part of the fender and rear are made from fiber glass.

 

Another guy just told me that Pontiacs use Urethane like the front and back bumpers and the Camaros use Fiberglass.

 

I'm almost sure they are polyurethane. The 82-84 camaros (Like mine) are fiberglass. And, yes, they should be pretty close to the same as the bumper covers.

 

I'll second the vote for molded urethane on an '86 - the same as the front and rear fascias and rear wing spoiler.

 

My 86 is definitely urethane. I went to numerous body shops and paint shops to veryfy as I was looking for ways to remove the dent from a previous owners accident. I used a heat gun with a small paint roller. Being very careful not to OVERHEAT IT, it worked out perfect, just took a bit of time to practice. The urethans apparently has "some" memory to it, so it should nicely come back to it's original shape with a bit of help.

 

Extremely dead thread but does anyone know if the the ground effects kit is thermoset or thermoplastic? Need to fix some deep cracks but my method depends on this answer

 

Kit? Don't know. Option kits and dealer-added aftermarket parts are a wildcard.

The factory options for an '86 Pontiac aero package (RPO W62) and rear wing spoiler (RPO D81) were RIM molded polyurethane, and as such were externally thermoset gels pumped into molds with polymerizing catalysts, and heat cured. Some of the larger and heavier panels, possibly the spoiler included, were two-part molds using a reinforcement in the exposed panel face and lower durometer core. They are comparatively not very rigid, but are forgiving enough to flex without fracture more than pure thermoset or GRP parts. Pure thermoplastic (TPU) for the spoiler likely would have deformed in heat and sunlight had that material been selected.

Fieros were a wild combination of RIM, TPU, GRP, and PE panels all over the non-metal bodies. I had three of them, and body work could be a challenge. Those started production in the 1984 model year, and a lot of the lech used in those was carried over to many other GM platforms. By 1988, most GM cars had a lot more plastic than previous versions, and they never looked back.

 

I'm referring to things like the lower spoiler on the 91 RS, I really can't tell what it is which makes me repairing it VERY hard

 

I'm unfamiliar with those other than seeing them out in the wild. Firebirds used a molded ABS air deflector below the urethane nose, and no spoiler at the front.