joel hunter wrote: > > anybody have an idea on the horsepower rating of a 71 413 rv block. im > pondering putting it in my imperial, but what combo of heads or manifolds > would i have to change? I don't know exactly your answers, but the replacement pistons for this motor, such as Silvolite #1272D, are deep dished and rated at 7.5(!) to 1 nominal static compression ratio. I've heard that the heads have additional water passages, which I don't see would be of any harm in your Imperial, but you may need some early closed-chamber heads to get any decent compression. Bill Parker, South Central Indiana '56 Chrysler Windsor; '60 Chrysler Saratoga; '62 Plymouth Max Wedge; '64 Dart Convertible (Kathi's car); '65 Imperial; '65 Barracuda \6 (Kathi's other car);'68 Barracuda Fastback 340-S; '69 Barracuda Fastback now 360 (20 y.o. son's car); '72 Cuda 340