I have a set of GT40 heads on my 5.0 with, well I have a complete GT 40 upper w/bout 2000 miles on the upper and 109,000 on the lower. Still runs great, just want to know where to get some info on the heads I have. They were already on the car when I bought it so I dont have the specifics on the heads. Are they all the same? Anyway, I am building a 347 DSS stroker W/sin turbo and am wanting to sell the motor I have now or part out the heads and stuff to sell. Just wanting to know what I am going to be sellin guys. Any info will help.....