Yeah, stock gasket and stock head bolts. It does scare me a little bit, I'm basically walking the thin line here. It only gets that high when I really put my foot in it. It'll jump right up to about 42 then slow a little but climb to 47, then it tapers off and slowly drops back to 42. I don't hit that high that often though, every time I do that I picture my transmission exploding.
27 ain't bad though, considering what these bad boys put out stock. Under 20, so I hear.
My truck can peg out the pyrometer I have installed. Its a 0-1500 degree pyrometer, and when I put my foot in it pretty good, it'll climb to 1500 and get stuck there until I let off. Lord only knows what searing temperatures I'm actually hitting. When my turbo falls off as a giant fireball and rolls down the road, then I know I over did it.