Trick Flow 440 heads, The Real Deal?

The valve center lines are not moved. They are in the stock location. The chamber will overhang the bore on a 383, but it does appear that the valves will clear with about .100" clearance to the wall on a 4.280" bore on both the intake and exhaust side. So it could work on a 383, just have to do some massaging of cylinder tops for the chamber. I wish I had a 383 block to mock them up on to verify these measurements, but I don't. If someone close has on and want to bring it out, that would be great. Then we can put this in the books.

But I still agree that the bore size should be bigger to help take advantage of the chamber and valve package. But it does appear they will work on a 383.