I'd do the metal spray. We have our clamp dies done to add traction on the benders. It's like a coat of sandpaper. It looks like cast and it will be uniform. Ace metalizing in Santa Fe Springs CA does our stuff. I'll try and get a number for you.
Maddog got this right. Go to Harbor Freight. Buy small or large needle scaler. It works well. Good luck
Wow so many good suggestions! I spoke to the local blaster and they said they do blast with steel grit. It will set me back about $50.00 for the pair. I did try the sandpaper thing with a hammer but it didn't work so well for me. I am going to paint the manifolds with Bill Hirsch cast iron grey manifold paint. I was thinking if I put a heavy coat on and imprinted it with the sandpaper would that work or would it lose it's texture with the heat? rc.Grimes: Can you provide some more info on this coating you use? Any names or contact info, where to buy, etc? Thanks so much for all the suggestions. I will be sure to post pictures with whatever I end up using to get the desired finish.
Use a needle scaler. Someone did this on a pair of CNC'd aluminum heads a few years ago and it made them look like stock cast finish heads. Couldn't believe it! I'll try and find a link/pic of it.
id set it on the fence and shoot it to **** with high powered air rifle and steel bb's or pellets. it'll gaurantee a very random pattern if its powerfull enough to make the marks
Ive had good luck with a pointed punch, hammer, and rough sand paper atleast on aluminum, might help to skim it with a sandblast
[quote rc.Grimes: Can you provide some more info on this coating you use? Any names or contact info, where to buy, etc? quote] Maryland Performance Coating (410)549-6122 I know they're not exactly next door but they will be able to give you first hand info on what to ask a more local shop to do. JetHot and a few others make coatings for the exhaust that do the exact thing you're trying to achieve but in a variety of colors and textures. The other bonus is it will hold up damn near forever. They did several fabricated intakes and headers that came out great.
I'm thinking all that would do is compromise the coating's durability. Don't worry about the smoothness so much, once the coating gets some age it'll have enough character on it's own. Good luck
On the same note, asphalt late model engine builders would cut intakes apart, work on them, weld them back together, and etch them with a type of acid. There were guys who'd guarantee that tech inspectors wouldn't discover their work. That was aluminum, may be a similar method for cast iron.
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