if you have a very worn cam lobe you prob have more than one. it cant run right if it has that. if several cylinders are running with less than a full charge of air/fuel then it might be getting very good mileage, but you wont have the power it should have. and it wont actually be running smoothly. if you are used to a four cylinder, for example an eight running on six with two weak may not seem to bad but compared to a good running eight you will readily see the difference.

i would be getting the valve covers off and investigating the cams soon.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.