5.7 Hemi Heavy Duty (HD) vs Overhead Cam Engine

So funny story, but someone did make a V8 Viper engine already (kinda). Conley engines was contracted to make some 1:4 miniatures of the original Viper engine for some promo stuff way back when. I know one exists, I think maybe 2 were fully built and parts have shown up here and there since then, but a foundry fire basically killed the project. However, since he had already done all the work he chopped two cylinders off and sold it as the "Stinger 609". So it's technically not the Viper engine, but you can definitely see the similarities. Gary Conley - The Miniature Engineering Craftsmanship Museum

So there is certainly some precedent for a V8 version of the engine...