5.5 is a copy of the only performance combustion chamber design by Ford engineering for the model A.6.0 is a modified heart design combustion chamber.
The stock model a ford engine suffered from two issues, low compression and inadequate fuel.Building true performance is a sum of all parts,the head will wake it up,a single V8 down draft carburetor (Holley 94 or Stromberg 97) flows air (CFM) at the same rate the engine does,matching CFM flow rates insures adequate fuel at all rpms. A late model B camshaft increases actual valve lift by over .030 and by design builds torque to 2900 rpm,as opposed to the stock A's 2400.
The engine in stock form is pleasant to operate, low rpm torque is what makes it feel good,hop it up? the torque rises right along with it. with a mitchell gear splitter I can be in 'full pull' from ten to fifty miles an hour, you can actually school some folks in traffic
