i have a '86 with the 351W. i bought some cheap sunpro gauges water temp/oil pressure/volts, and i installed then today and founf out something interesting. i started the cold motor and the oil pressure (high idle) went to around 45 or 50 and once it warmed up and had a warm idle the pressure dropped to 0 and at about 2K rpm's it goes to 15 or so. my question is if it was really zero how would it not ruin the motor? it has idled like that for about a total of 2 or 3 hrs and still runs ok. you think something is wrong with a gauges even though it show about 50 at cold idle?