I have a set of Blue Thunder heads in my shop that are unlike any that I've seen before. They are aluminum and have a Ford exhaust port that is not raised the way that most of them are. The floor of the exhaust port is tilted in the same way as the Edelbrock heads. The combustion chambers are unique also. Instead of having a heart shaped chamber, they seem to have a tight dual quench high swirl chamber. The heads came with undersized guides and without a valve job. As soon as these things are done, I will flow them and post the numbers. I also have pictures that I will post later.
Alvin
Alvin