and could this be a tunning issue for a loss of power?

it could be or since you got a Hi-Flow intake, it could be the MAF.

get on the dyno with wideband o2

Also how's your gas mileage? Take out your spark plugs look a tthem. If they are black and smell like fuel your running super rich.

This may be a shot in the dark, but if you know someone with a SNAP-ON Scanner, it will tell you exactly what is going on. I will actually say "LEAN" or "RICH". It would be good to also know what mV your 02 sensor should read and compare it to the scanners reading.

After a while, your exhaust pipe will be black as well.

Gas mileage is Ok 350-360 miles per tank. Mufller tips is pretty black and I have not checked the spark plugs yet. But I did notice that when I floor it and some one is behind me I see smoke. How can I fix this?

Dyno would be easiest...or an AF gauge (wideband)