Not sure why everyone keeps bring up the 481X deal. That is NOT a block that takes a Mopar head. It takes a 481X head, which is an Oldsmobile wedge head. Also the block is a 4.840 bore space and takes a Chevy crank. Basically a Chevy block, with skirted sides and provisions for a front drive dist. It LOOKS nothing like a Mopar block.
A TFX block is a HEMI block. A TFX or 481X block can be forged or billet
Why not bring it up? There are no current "Mopar" blocks to use and us Mopar guys get poo pooed pretty hard for being hung up on stock looking heads and purple cams. I brought up the 481X because it's a cool engine, and to me, I see a lot of Mopar in it and was just trying to expand the conversation. If someone made a "Mopar" head for it you might see some hardcore Mopar guys using it. Again I understand it's pretty much a purpose built engine that's a mash up of Chevy and Hemi BUT something like that might be enough to get the Mopar racers going, maybe not, was just a neat package that I've always been intrigued by. BTW apparently they used to make a cast block, which I'm guessing had water jackets?
