[mgarblik]

If you decide to go with an aftermarket block like the IAII, I would throw my vote in for a 541. The 4.375 bore and the 4.5" stroke is super sweet and many different combinations have been built for years now. I often felt that if I still had my 66 2+2 convertible, at 4270 Lbs., this is THE engine I would build for it. It was a blast with the 421 HO, but oh what another 120 CI would have done for it! 541's are easy and with the low cost Chinese cranks are not too expensive. A 600+ HP engine that would idle smoothly at 850 RPM,s and tear your neck off your shoulders with all that torque sounds like the ticket to me.