Hey guys, Im interested in casting some custom one off exhaust manifolds and was looking for any info regarding doing it or maybe a guy or shop in the Nor Cal/ Sacramento area that can do it for me or help me do it. Ive checked out a few sites regarding backyard foundries but nothing really pointing me in the direction of casting an exhaust manifold. Id pay for it to be done but I can only guess that itd be insanely expensive. There is that other thing of doing it your self type of satisfaction but for this project I either cast it or spend A LOT of money on tubular headers (its gotta be thick cast iron or stainless steel for tubular). Id prefer the durabilty of cast iron for what Im going for. Also casting a few sets outweighs the costs of welding up stainless if it cracks. For the nosey Im being asked to put some turbos on a 32 with an LS1 that wants to rip it hard reliably. Theres a few companies that make manifolds but they are 5k for one set!! Figured I could have some cast and have a few left over to sell for that price. Also if I learned to do it, may be able to do other parts. Im just looking for info or leads on who can help or how to do this. Last time I poured metal was in high school and I was making Al Skull shift knobs...
i've had a couple things outsourced at foundries in the past: not too cheap at all... but after trying to cast a single exhaust manifold for a turbo setup, i'd say the cost to outsource it may not have been so bad. casting aluminum is a lot easier/funner. i'd consider weld-els (mcmaster carr or grainger), 1/2" mild steel flanges... and ceramic coating.
You might want to contact Doug Dutra. He hangs out on the slantsix.org board, and is one of the most technical guys about a slant that you can find. He also happens to live not too terribly far from you. He has gone to the trouble of making the molds and having cast split exhausts for the slant six motor, and if I'm not mistaken, one can buy both back and front halves for about 5-600 bucks for the pair. Roger
I suspect the actual casting might be the easiest problem to solve. Getting the patterns including the cores might be more of a trick. Although I have seen some incredible work done with the newest 3-D modeling techniques. I did a couple of quick Goggle searches and there are some foundries in the areas you mentioned. Seems like there was a HAMB thread about an old school foundry in the Oakland area, search quickly but didn't find it.
Start by finding a foundry that regularly uses cast iron, will work with loose patterns, and in small volumes.
No need to get all offended, because I don't see the need for 3D modeling to produce a sand cast manifold. And that is useful information.
Yeah casting iron is an old process. The patterns are the key though, without good patterns you won't have much. If the guy is making an oddball set up, but could draw it or have it drawn in a new 3-D type software the newest technology (as an example: http://xlaform.com/pdfs/Creating_Rapid_Prototype_Metal_Castings.pdf) you can produce the patterns more quickly than the traditional carved and formed castring patterns. Probaly still not cheap though. Then you'd need a foundry... http://www.thomasnet.com/northern-california/cast-iron-41311259-1.html
The Jalopy Journal
