Comment by drzaiusx11
23 days ago
My experience is limited to cars manufactured before 2008 (back to 1928). Maybe the new ones are all welded cold rolled steel tubes but I've only seen cast parts for intake and exhaust manifolds, nearly universally. Shit cracked all the time.
This isn't a new thing. Jeep used "factory headers" on the last years of the 4.0. Ford did welded manifolds on the 5.0 Explorers. Subaru went to welded steel for the EJ series engine in the 90s. GM had them on the LT5 in the early 90s. Just about every application that has the catalytic converter right up at the manifold used a welded one.
I recently worked on a 2008 ej25 and it was definitely a cast manifold. Possible we're mixing up terms? Maybe you meant the ejs are cast steel instead of cast iron? When I read "welded steel manifold" I think of perfectly cylindrical tubes welded to steel plate for the mounts. Likely we're saying the same thing and manifolds are just cast parts that are welded together
Note that the one I worked on was in a US Forester so definitely not stock parts (j is for Japan)
EDIT: link to example 2005 manifold listing on eBay
https://www.ebay.com/itm/157306917967