dareo wrote:If you're going turbo go iron, if your going N/A go alumanum. Thats my opinion anyway.
Go aluminum either way... remember your pistons are an aluminum alloy. There is no reason not to go aluminum for a block, simple pressure casting of aluminum can yield a material that is ever bit as strong as normal cast iron. That VH block would hold more power than an RB26 stock block any day.
And for anyone thinking the RB series engines are heavy because of their block, you need to take a good look at one. The block itself is about .5 - 1" thinner in width and about 1-1.5" shorter than a KA24 block. Keep in mind it's only displacing 200cc more than a KA. The weight comes from the extra head materials, reciprocating mass, manifolds, turbo(s), etc.