I replaced the original camshaft in my 408 with one supposedly identical in specs (the original cam had lobes going flat and was defective). The car ran great with the original cam but with the "new" cam, it runs terrible using the same tune.
After replacing/checking every component on the car, I had a hunch the camshaft wasn't exactly the same. So I sent it off to comp cams to have them respec it and sure enough, all though it is close...the specs are off. The duration on the inake and exhaust is 3 to 4 degrees off as is the lift. (original cam was 232/240, "new" cam is 229/236 duration. Lift went from .355/.360 to .349/.355) Could this explain why the car runs so terrible now( using the original tune)? Is a new tune in order?
After replacing/checking every component on the car, I had a hunch the camshaft wasn't exactly the same. So I sent it off to comp cams to have them respec it and sure enough, all though it is close...the specs are off. The duration on the inake and exhaust is 3 to 4 degrees off as is the lift. (original cam was 232/240, "new" cam is 229/236 duration. Lift went from .355/.360 to .349/.355) Could this explain why the car runs so terrible now( using the original tune)? Is a new tune in order?