I have run and built a few of them, the 40+ years between the designs show. They are designed as regular mass produced engines, and not to be an all out race engines. However, even in Stock form they run decently. I have been to 11.0 with a mild cammed 6.1 in a '71 'cuda, stock intake, heads etc, and you can drive that thing any where. Currently installing a 6.4 in to a series2 Jaguar XJ6 with the ZF 8speed. It weighs 4000, but I expect it to run decently. The drivetrain is stock. The left over 2004 5.7 in the car, I have plans for that one too. Will rering the short block. I cleaned the ports in the stock heads without making the ports bigger,had them milled .040" and they flowed 280+ cfm. I will use a short "drag pak" intake and a 750 holley with MSD ignition, and a cam/timing set up / springs from a 6.1 SRT. Will get it dynoed when it's ready and we'll see what you can get out of one in the real world and low budget. I'm not a huge fan of the gen III's, at least not yet. The reason being the availability here, the big physical size (wide), the lack of reasonably available aftermarket parts (compared to LS), and the difficult to modify stock ECU's and lack of cheap wiring parts.