Hi all,
I'm about to mate an EJ251 from a 2000 Impreza RS to EJ25D heads from a '98/'99 Outback. I was told to utilize the head gaskets from the EJ251 (very thin) to bump up the compression. I was also told that I needed to use copper sealant on the HG's. I'm not sure why, the shop didn't have the time to explain to me... Looking around the other subaru forums, I've not seen any mention of copper sealant being used for ANY application, be it stock or hybrid. Ideas? Is there a difference between the Permatex Ultra Copper RTV and Copper sprays? The RTV states that it is rated for 700 degrees farhenheit. . .
Take care,
Greg.