I'm late to this party on this thread, however, regarding weight I weighed my 69 Cuda's iron 340 when I pulled it out, and weighed my new 468 iron block/aluminum water pump housing, aluminum heads, and aluminum intake before it went in the car. The 468 weighed 71 pounds more than the 340. Replaced the .750" torsion bars with 1.03" bars and the car corners as good as ever AFAICT. Sure is faster though! 4.350" bore makes a lot of torque.
