I am considering purchasing a 70's-vintage Luhrs 32 sedan with flying bridge that has twin 318's. I am curious as to the fuel consumption of these engines at different boat speeds. Does anyone know of any tables or charts that might correlate engine RPM, boat speed and fuel consumption? Absent that, can anyone give me some idea of what kind of fuel consumption rate I can expect? As old as this old gal is, there must be somebody with experience in this. It is not a deal-breaker, just another piece of data. Thanks.