My current cam in the 351w is too small. It is a TFS stage 1 with 1.7 roller rockers. Ideally I would like to go with a custom cam but my future plans would be to build a 393 or 408. It would be at this time that I would go custom. Anyway, the cam is too small and I want something with more grunt. It runs good from 1500 to around 4800 but seems to drop off after that. I would like something that would pull good into the high 5,000 range or low 6,000 range. I do not remember style valve reliefs are in my engine. When I purchased the engine (online), the builder told me that it would accept the z303 cam. However, with 1.7 rockers, I am unsure where to go. Any thoughts or suggestions would be great. Thanks