512 B build almost complete

80fbody said

From Hughes Website:
1. The E-Street head uses a less expensive (a little heavier) valve than the RPM head.
2. The E-Street head has powder metal valve seats whereas the RPM heads use ductile iron seats, which in our opinion is a better seat material - it is harder and lasts longer but is harder to machine.
3. The E-Street heads do not get hand blended valve bowls from Edelbrock. The RPM heads do.

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Disagree with 1. and 2. I find it very difficult to believe that Edelbrock would employ a different valve between their entry level heads--The part number on the tip of the valve is 27653 GR. Number 2 I can certifiably dispute. I know how a powdered metal seat machines vs a ductile iron seat. They are NOT powdered metal which is surprising because I'm sure powdered metal is less expensive. Edelbrock is a volume production manufacturer-they are going to order guides,seats and valves by the thousands--they are not going to distinguish between powdered metal and ductile iron seats--they are going to choose the vendor which is the least expensive-same goes for valves. 3. I don't really know or care about. J.Rob