Speedmaster heads out of the box flow better than Edelbrock out of the box heads and look 100% better. The one and only complete set of heads I bought from speedmaster were set up for a hydraulic roller cam. They cam with hardened valve spring shims, 10 degree retainers and keepers, and until that one head looser valve guided than Edelbrock heads which I’ve found some tight ones. I also discovered over the winter that the Speedmaster heads have more clearance around the intake valves and a nicer finish which really helps with the .100-.350 flow numbers. The valve springs looked very nice and had enough shims to use for a customer running a smaller hydraulic cam saving him money. I’ve never heard of anyone breaking a Speedmaster valve yet but I wish I knew who made them. I’ve heard rumors who makes Edelbrock valves but have never found proof. I think buying complete sets would help eliminate the issues I had with the one bad set I’ve found.
