As a fellow who truly understands the idea of making the underdog into a winner, I totally empathize with your train of thought. Where we differ is in the reiteration of two old sayings, "Bang for the buck" and "No replacement for displacement". If you want to run a 248, by all means run it but if you're trying to turn it into a 270 by replacing the stock crank and over boring it. Are you really ahead of just using a 270 to start with? The 302 head is vastly superior to the small port head for the very reason you stated, intake port. It's needed to support the larger displacements. If you truly wish to run the 248, why not rethink your battle plan to utilize it's strong points. Shorter stroke and smaller displacement. The long rod, light piston is great. That plays into RPM. A smaller displacement also allows you to use that head as it doesn't need to flow as much. You would end up with a small "crisper" engine. As far as the cams go, have you measured the contact area diameter on the VW? If it is the same or less than 1 inch (stock Jimmy) you have gained nothing for your work and lost the bearing area of the lifter barrel. If it's larger, how much have you gained under the curve? Your analogy is a little off, we think in terms of "Why start with a Shetland Pony when a Clydesdale is needed?". You have some excellent ideas and some contradictions within them. You are absolutely correct about the Jimmy being superior to the Chevy. That's why my next engine will be a 302 using a 248 crank. Of the people who post here, Bob Corbett and Ron Golden have built the best Jimmy's out there. When they talk, I listen!
