Mike I am really interested in this set up. Is it just a matter of cutting the grooves and extending the holes of the spacer down lower into the intake plenum?
What kind of results did you see with the motor home engine? I am building a 440 with 413 RV heads now for my Travco RV. This MH engine has coolant flow through the intake and crossover ports in the heads. I was thinking about blocking this off to help keep the fuel and air charge cool to help prevent detonation.
Seems from reading your posts I might be better served to keep the coolant flow open to help atomization of the fuel charge and suppress detonation that way.
