I had AE in my last engine when I stripped it down. I was told they are cast. Mine were in very good condition even after 2 years of my driving with nigh on constant use of ALS and LC. It ran with greys and 36psi on my t34.63 and for however long they were in with the stage 3 set up before I bought it. Not overly useful info but thats all I can give you on my experience with them