I have been researching this topic and was looking at pros and cons. Here are a few threads:
To Powder Coat or Ceramic Coat, that is the question?
Powder Coating In this thread the OP answers a lot of powder-coating questions.
My goal is to paint some or all of the below parts (At least upper valve covers, fan and shroud, fuel rails, plenums). I would be looking for a natural aluminum/silver (not gunmetal, not chrome). I might go Speed yellow or similar for the fan. So far all parts have been dipped at the machine shop to lift the major grime.
So here are my options:
1. Bead blast: cheapest (~150$ by the machine shop). Would look great at first, but would eventually corrode again. This might lead to obsessive polishing.
2. epoxy paint (crinkle paint or other): I have a local body shop that could do this for me at low cost. Pro's seem to be ease of re-application in case there are chips down the road. Down side is durability. Not sure I would want to clearcoat on top of this as it is known to discolor and flake.
3. Powder coat: Getting more expensive as specialized, but I was quoted 460$ by a local powder coater who works mostly with bike components. Downside is difficulty to touch up any future damage to the powdercoat, and difficulty removing. Touch up should not be a huge issue if the color I choose is a metal color anyway. Heat can warp mating surfaces, requiring leveling. Not sure if this significantly effects heat transfer.
4. Ceramic coating: Same quoted price as above. Similar to powder above, but less color options. I would not do for the magnesium fan housing as my local ceramic coater uses high heat curing ceramic. Warping may still be an issue. Some advise against for valve and timing chain covers as it can lessen heat dissipation (good for headers, bad for engine parts).
Edit 5. Leave it alone!: A car is original only once. Clean it up, get rid of the oil and grime, maybe scotchbright things up. Advantages are cost and originality. No metal lost to media blasting.
Reminders to keep powder coat and ceramic out of mating surfaces, internal engine surfaces, and screw holes (can effect torque specs).
I am looking for experiences/additional pros/cons of each, and I am wondering what is the best media prep for the final 3 options.
thanks for any help