400/406 Builds

[Marv D]

Nick, I saw a set of cnc ported 186 casting camelhumps that were built for a friends small cubic inch dragboat went 218/137 @ .6" lift on a Superflo SF600 bench. That was with some spec they had to live by limiting the port to (best my memory recalls) at 165 or 170cc (something like that),, where they start at mid 150ish cc in stock, as cast form. I remember Roger saying some of the castings they started with went almost 200cfm as cast, but the sloppy casting and inaccurate means of the day,, the #'s were all over the place.

I've seen some of the reports around the net that they got 461's and such up to 260-270cfm with ultra secrete trick cnc programs,, but I've never seen anything but 'internet' claim those numbers.

In short I'm not trying to bash anyones machinist or build, just saying a 400 inch motor is BIG cubic inches and using a head designed for 327 inches should in it's self offer some thought of it's limitations.