GT40 heads are really only worth porting if you can do it yourself at this point. If you think about it....you pick up the heads for what...$200. Spend another $700 on a good port job and you're into the heads far more than they're worth. I got my GT40X heads fresh from the machine shop with new guides, valve seals and a fresh decking, with a little port work done to them already on top of it all for $700 shipping included.
With stock headers, most likely yes. But, with a lot of aftermarket headers, you're able to run a 90 degree spark plug boot and be okay. Or you can bust out the torch and some big as* channel locks. Had to do that on my Bronco lol
I had MAC shortys that worked also. Good idea to buy protector sleeves also. I learned the hard way on that.. Stupid wires were arcing off the headers because they were so close.. Bought a set of eBay sleeves and problem disappeared. Prob 25-30$ well spent, plus they keep your wires from getting burnt. They can lay right on the header with no problems. You will most likely need to modify a spark plug socket for a couple of the plugs.. Unless you put the plugs in before you bolt the headers on.
