[QUOTE=disclaimer* i can not yet PROVE the fusion block is not aluminum. what i can prove is the fins surrounding it are aluminum which is expected but the block itself never allows the water to touch that part of the cooling system. i took a good hour when i received the board looking at this very carefully trying to figure what it is made out of and weather it comes in contact with aluminum. i started scraping at the fusion block and got a small piece off and there was no aluminum under it. the fins on the other hand to the left of the block are painted aluminum anything slightly sharp will scrape the paint off.[/QUOTE]



Today I port matched the Fusions block inlet/outlet to the barbs i.d. Got copper shavings in the process. The block itself is copper "not" aluminum.