The Hesco head is $1,995.00 I used one on my 4.7L Stroker I built in 2002. Using that head with the 99+ Intkae Manifold and a 68mm Throttle Body (from the 4.7L V-8) plus a good camshaft gave me an honest, at sea level, 300hp. Up here, of course, it was less. It's an altitude thing...
I purchased mine from Patriot Performance (part of Alabama Cylinder Heads) but they no longer sell it. Hesco is the only sorce. At the time, it was available in two forms and I grabbed the big valve version as I was building the big engine. I also went with roller rockers. One of the better ideas on this head is that the valve cover mounting area is raised by 1/2" to allow the use of the rollers. On a stock head, you have to install a spacer that although it works, it doubles the opportunity for oil leaks...
The head itself is completely redesigned. The ports, combustion chamber shape and size have all been changed. Keep in mind that the engine is a system. If you go with the head, then the manifolds, cam and the throttle body needs to be optimized as well to take advantage of the addition flow capacity. If you strangle the head, you are not going to get all you can out of it. Another advantage is temperature control of the combustion chamber as the aluminium conducts heat away sooooo much better that cast iron...
Way back when, I was on JU. You might still be able to find the my thread on adapting the V-8 TB to our 6. Not hard, just time consuming... The V-8 TB comes in two flavours, 65mm and 68mm. The 68mm is on the Magnum engine.
If I was not in Retirement, I would buy another one in a heartbeat to get more out of the Heep. Of course, this time I went with forced induction instead of more physical displacement.
