Need some advice 318 POLY vs 318 LA
based on everything I've seen on them, can be built into GREAT truck motors with tons of torque with the parts that interchange with LA motors as listed above. Can also be built into high performance motors but you will likely need a lot of custom parts along the way to get you there.
Less availability of parts, larger footprint, more weight... vs LA motors
But IMO, they have some of the coolest valve cover designs out there with the saw blade look