Looks like MP was trying to duplicate the burr finish that some of the head porters use these days?
They sure felt more like the gravel in my driveway than any type of burr finish.
Even the coarse non-ferrous burrs I was using to rough in the ports left a smoother feeling finish that how these were as cast.
The odd part is....... the roughness was really confined to the inside of the ports.
The exterior of the heads is much smoother.
I’m pretty sure the 58cfm gain at .550 lift will pay some dividends.
