lets say you try to amortize it over 100 units, that tacks on an additional $100 per unit to the price. This is already a price sensitive market as it is...
And in the case of MS manifolds, that's not easy, they can't patent the idea of a "bigger than stock manifold" since that isn't exactly novel. The best that they can do is patent certain specific dimensions, if they can show certain improvements due to having those dimensions. But then all that needs to be done is to make something 0.1mm different, and you'll have trouble enforcing the patent.
