340 Initial timing questions

It's not about compression. It's about cylinder pressure. If an engine doesn't generate a lot of cylinder pressure, it's going to want more timing than one that does. Did you degree the cam in? I "just bet" that cam would run better and require less initial timing if you installed it a little more advanced than what Lunati recommends. Have you run a compression test? I bet a dollar it's under 150. While Lunati might say to "not worry" about what your compression is with that camshaft, it will perform better "with the right amount" of cylinder pressure.......which is not the same as, but is affected by static compression ratio. 9:1 static compression is "a bit low" for that camshaft. That in and of itself is the reason you're pulling in so much timing. That's not necessarily a bad thing. If it runs well and you're happy with it, run it. Just know that it could be "more efficient". ......but then........whose build couldn't? If you worry yourself chasing every little bit, you'll never have any fun.