74 360 4V questions

My son and I was replacing his flat purple cam in his duster today and noticed that it has dual valve springs on it. This is a stone stock almost 19K mile engine..yes YOU READ IT RIGHT..less than 19K miles on a 74. He got it a few years ago for $2,000. Took the heads off today to check eveything after the purple cam that was put into it went flat after about 3 Hours of running it. The questions are ...this is a police motor in it and does it supposed to have the dual springs on it? It has J heads and absolutly no ridge at all in it with the standard bore. Any good information on this year engine and its rareity would be helpful myself and my son Matt.

Jeff

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Author: admin