Ain’t nothing wrong with ported iron except the bill due at the end of the day. It’ll be worse if they don’t flow better than the ported head offerings.
I agree, generally speaking. Full on deal, takes some time. I think the sm is a good deal for a builder , not joe schmoe.
Someone that knows what to do and has the tools. Otherwise they are a lighter head with a better exhaust port.
As for what I was referring to with some 'blending' is not much work to get 1.94 working 250cfm and the rest of the numbers are better than a speed disaster head, however. Ootb sm 171cc low lift is marginal. The .400 and up okay.
It's not as clear and simple as people think.
So it really depends on what exactly we are talking about, what level.
