Yeah,you'll need a piston with a comp. hgt. of approx. 2.470", might check with Venolia or Ross and others to see if their forgings can accomodate that much length. If you could find a set of real long rods like Ron used in his 320 GMC combo, that would help with finding a comp. hgt. more doable by the piston companies. I doubt you would be able to stretch the rods without hurting their structural integrity.
