Reply to "Wide and Flat Torque Curve"

Doug Its not a dyno trick. These heads only call for 28 degrees total timing, no matter what the compression ratio is. These heads will easily run on a 1/2 point more compression than the original combustion chamber design; in other words 11:1 instead of 10.5:1.

Scott the main thrust of Darin Morgan's design is not gas velocity. That's always a component of the design, its just not something you and I should have to worry about if the designer does his homework, however gas velocity is kicked around a lot in magazine ads and what not. The heads designed by Darin Morgan have about 249cc intake port volume, a ported iron 4V intake port is about 250cc. The port entrance of the 4V port is deceiving, the port gets much smaller further inside. Darin Morgans port has a much more constant cross section. But the two ports have about the same average cross-sectional area. The 4V port is designed the way it is because the Ford engineers were doing some gas management tricks that worked quite successfully, Darin Morgan's port is a more "straight forward" port design. The 4V port is tuned for a powerband of 3000 to 7000 rpm, the lower end of the 4V powerband relies upon camshaft design & intake manifold design. I can't say what the powerband of the SCM heads is. Both are designed for wide flat torque curves.

The computer is turning off.


-G