Randy, I noticed some pictures in the users gallery about a V-8 Skybolt. Is that the 215 Buick Aluminum V-8? I thought you menitioned that you used V-8 Chevys? What's the Buick 215 like? In your previous post about auto conversions you mentioned that auto engines seize-up. There are a lot of corvair, subaru conversions out there that snap cranks, is that true of V-8's? I figure a V-8 would be a bit stouter. I would think if it is, than you can extend longevity (sp?) by reducing the rpm's and reducing torsional vibration. I would think, that one can reduce rpm by bringing the torque curve up into a lower rpm band by changing the camshaft profile. And maybe one can reduce vibration by using contra-rotating props (using a shaft within a shaft). Any comments?