Wow, I think it's your best artwork so far! Only thing i Don't like is the text, but that must be a defect from your native job(tattooing), next time choose a bold and simple font.
EDIT: And I've noticed on your chops, the mistake you make when pasting intercoolers, I think you change the blending mode and it doesn't look proper. Search for proper IC donors, c/p them and don't adjust anything except bright/contrast or levels! Makes it more real.