Smoke goes from black to white
 

I just recently put a stack on my truck and i wanted see if it smoked much and put my chip on 80 and in 4th and 5th gr over about 1700 rpm the smoke changes from black to white. What causes this?

white? or gray?

White would indicate fuel or oil issues...

gray would be normal.

It looks more whiteish to me when i look out my rearview mirror and i have 20% tint but I dont think that would make it look a different color