Let me explain my situation. I am taking a sculpture class at school (which has a foundry) and at the end of the semester we have an Iron pour. This affords me the opportunity to do cast iron work.

Well I was playing around with the idea of making a few cast iron manifolds. I've done this many times before, and have made molds for some pretty complicated forms. So, I know how to make the molds and cores, but I need some information on the make-up of the iron.
From what I can tell, most manufacturers of manifolds use a high silicone iron. In my class we use old brake rotors for the melt.
Is the silicone content of the rotors enough for the manifold? If I need to add more silicone, how much should I add?
What else should I be looking out for (ex. carbon content, etc)?

Any info would be greatly appreciated.

 

Why not just use old oem cast exhaust manifolds for the melt.The salvage yards are full of them.
Glenn

 

Thats a really good idea. I wish I could, but the pour isn't just for me. We will probably be pouring about 1 1/2 tons of iron that day. Rotors are used because they can easily be broken into smaller pieces (easier to melt). The amount of work it would take for me to prep up enough oem manifolds for the melt wouldn't be worth it.

 

The rotors will be fine. Rotors are used in high heat situations with low expansion. Sounds like good properties for a manifold.

 

yea that makes sense. Thanks a lot.