Big valves hurt flow more than anything  
        "2.02/1.6." If no chamber work is being done 
        stay with 1.850in/1.55exh.valves.If you are
        going to do chamber work then 1.94/1.6 can be
        used..CAUTION 1.6 valves must have a flaired
        port because the exhaust port slims down about
        3/8" down the port on the water jacket side and
        if you cut or gring out too much metal the port
        will crack in this area.If you are going to do
        chamber work, copy the new style GM small block 
        heads on laying back the chambers,this will get 
        you in the ball park, flow-bench R&D has proven
        that this works.

           Flow bench CFM @ 25" GM inline with 1.850
         Intake valves.
         Intake head bolt boss removed and pocket ported 
         and valve guide contoured. 

    Intake @ .100 =  58.7    Exhaust figures coming soon.
             .200 = 113.2
             .300 = 151.2
             .400 = 186.0
             .500 = 189.2
             .600 = 196.6
             .700 = 197.5

            Corrected to 29.92/0 R.H./60 deg.

            

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