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Made an interesting discovery on my 86 LA 318 out of a diplomat (which is now in my truck) today. All the research I had done on roller cams seemed to indicate that roller cams did not go into factory 318s until 88, and of course Magnum engines are roller cam motors. Even Allpar.com stated this. Guess what? I have one that tosses that theory! In 1986 dodge diplomats with engine vin code 4 or P had roller cams! This was the heavy duty 318 (4) and the 2bbl 318 (P). The irony? The vin code S (4bbl 318) did not! It was flat tappet! So when you go junk yard diving don't overlook those diplomats! Now, I do not know how far this oddity goes. It may be only that year and model, or it could be across the board. Anybody else able to confirm or deny this? Oh and I have seen the inside of this motor, it was a FACTORY roller



Civilian M-body cars went roller in mid-1985, so all 1986 civilian model Diplomats had roller cams. M-body 4BBL cop cars (Diplomats and Gran Furys) had roller cam blocks after the civilian switch, but continued to use flat tappet cams through the end of the run in 1989. LA 360s got roller cams in 1989, so maybe that's the cause of the confusion.