After trying to do some research I came up with some information but not nearly enough to really answer this question. Being that I am not a tuner I have no idea what the ins and outs are as far as setting knock, misfire, or anything else to that nature. Recently I picked up another fbody. Car is a cam only car with supporting mods. Lifters, springs, push rods, so forth. The cam is a Speed Inc Si5 camshaft. Here is my question:

Car runs great, idles up and down a little bit until at OT but other wise idle is clean and clear. Car pulls amazing in all gears, granted I have been trying to keep my foot out of it. The CEL is on for a random misfire. Now the previous owner told me the car was tuned by a local guy in NC that was known for tuning ls cars there. Of course...that tells me nothing. Is it possible that this camshaft can throw a false misfire that needs to be set/adjusted in HpT? I had read somewhere that once you get near the 600 lift area that this was possible but I am trying to get better information from someone that has delt with it first hand. Again the car runs great, doesnt miss a beat, and will pull like a train, which if it WASN'T tuned I feel it would run like ***. Car will be getting retuned come spring, just trying to do some home work.

 

Lift has nothing to do with it. Overlap of the cam is what you're looking at.

You'll need to reduce the sensitivity in your misfire tables. The PCM can see a cam as a misfire event. There are three misfire tables in the LS computer for low, medium, and high rpm. With a cam, you just max them all out to 32767.