Header crack

[BADINBLACK6]

My friend's GN has a header crack, I believe it is at 3/5. What problems could this cause?
He just bought the car and It is not running well and I wanted to find out if this could be the problem.

 

[Mr URL]

Common as all the Mustangs in this world. Get it welded up by a good welder. BTW - it's made out of a low grade stainless steel.

 

[strikeeagle]

gidde up, gidde up, gidde up 409...