That's why I asked. They seem to make considerably more power than the TW of old.
While I'm sure that the new heads are an improvement, I don't know about the way more power thing.
People are getting better at making power, no doubt about it. But people are also making more power with older stuff too.
Many Renegade and Drag Radial cars ran mid/low 8s with the old heads, several years ago. Hell, a member here ran mid 9s N/A with a factory block and crank 306 with a set, and low 9s with a aftermarket block stroker before a engine failure took it out. There is a member on several other forms that ran high 9s with a set of unported 170s on a 408, N/A.
As far as I know, the old school Renegade TW heads are still the badest stock intake/exhaust port location heads out there. There may be something out there now that is actually better, but those are some tough shoes to fill.
Plus, people are running the 11r 185 head where they used to run the as cast TW 170.
I have a set of those old Renegade TW heads. They are really getting on my nerve to do a small inch high compression, high rpm, E85 build with them.