roblav

2 layers of fiberglass on each side of the rusted tin, with black pigment in the epoxy, will create plenty of strength. The black pigment is there so you don't have to paint.

The last diffuser I made for the racecar has 3 layers of fiberglass / epoxy on each side of 1/4" foam. That diffuser provides about 3-400 lbs of downforce, and I can stand on it.

If I was making engine tin from scratch, I would use S-glass before using EGlass and/or C/F - for the cost/strength/heat resistance capabilities. You have to think about the strength required in "point / node" mounts.

You could use a good engine tin as a mold - wax it up, fiberglass/epoxy/vacuum bag it then trim it - voila.

meek

Well, if someone can supply me with a good, clean set as a template, then I am sure my local fab. shop could make them in anything. But, that is the problem; having a clean set to work from.

cobalt

It's not the steel it is the coating that fails. Whatever coating Porsche or their supplier used did not hold up well and once it flaked off the steel rusted exposed to the elements and heat. Unless you have holes through the metal i would just grit blast and repaint or powder coat.

My C2 sheet metal looked like crap when I removed it I thought it was shot. After blasting off the rust and old paint they looked fine and a simple coat of high temp paint made them look like new. So inspect them closely before replacing. Might find the cost for paint to be easier on the pocket.

i would also caution about using fiberglass. It does not hold up well in the high heat environment and unless it is sealed all around, moisture will get in between the layers and start rusting the metal from inside. If this happens it will start to break apart over time and get far worse. Although it could be done with good results, you are better off using the piece as a template and using a release agent to build a single piece of fiberglass to make a copy of the part and then using that. It would probably last longer although longevity depends on use, environment and how well the job was done initially.