I had a local machine shop set my engine up, and I just starting having problems with car running bad, and when I took it apart, there were 3 broken valve spings. These springs were bought brand new and installed by a machine shop, they have about 400 miles on them, and 400 easy miles at that. I won't be able to talk to the shop until Monday, but what do you think would cause them to break? The push rod length was right, I checked it and they did at the machine shop too. The heads were just freshened up, every thing in the valvetrain is brand new. They broke up towards the top if that makes a difference. Also I had my oil analyzed, and there were no large amounts of metal in it, and the guy at the lab said that there is no signs of problems in the oil, and the viscosity was okay also.

 

It was the quality of the spring material or they were being severely overworked or they were not installed at the proper height. Take your pick.
It had nothing to do with the price of the spring. Comp Cams springs have a rep of breaking on most of their better quality stuff.

Beehives are different and have not heard of any chronic breakage.