you are both spot on. I'm also doing a 400/470, assembly in 2 weeks. I've done the calcs to bring 600HP, solid stick, the new Trickflow heads, RPM intake, 830 QF carb, forged stroker kit, adj. rockers, etc.
Ways to shave costs: re-use some parts- valve covers, air cleaner, oil pan, heads, rods, rockers (depending on build), own assembly.
The totals are $14/HP to the dime. Pretty much every part is new except the block & I'm assembling it. Do the math= $8400. Then there's the trans, converter, d.shaft, rear end, on & on (another $7000).
The weakest link will break, so building one part= building the rest- relative to the HP. Stock parts don't go beyond 300HP, especially 40 year old stuff! Unless you are doing a science experiment to see what will break first.
With shop labor now costing more, gone are the days of $2000 engine builds.
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