"Spring mass is kind of like feedback," says Godbold. "A heavier spring means more load on the system. Then you need more pressure to control the additional mass of the spring. But if you do the opposite, the result can be exactly the same thing. The more mass you take off the spring, the less load you need to control the valvetrain. So, if the required loading is less, the spring doesn't need to weigh as much to give you the pressure you require."
Chasing weight has led to a change in philosophy among many engine builders and component manufacturers. A perfect example is Comp Cams' new beehive valvesprings. Instead of heavy, double springs which have become the norm in racing, the beehive spring is designed to cut the most weight possible. The beehive design uses a single spring, cutting the weight of an inner spring as well as a metal separator. Its top coil also has a considerably smaller diameter than a conventional, cylindrical spring. That smaller diameter means a smaller retainer is used to hold it in place, cutting more weight. So, in a properly designed system, a single beehive spring with its lower spring pressures can do the same work as a heavier double spring with higher spring pressures.
Even if you are using a more conventional spring, you should consider the spring's mass when making your selection. Advancing technologies in manufacturing have enabled single-spring designs that are stronger than ever.
"If you are running a class that requires stock-style hydraulic lifters, you should be fine with a good single-spring design," says John Steely of Howards Cams. "Unless you are running extremely aggressive ramp profiles on your cam, a single spring will do the job while limiting weight. The one exception I can think of is a class that has valve lift limitations. In that situation, you normally run a cam that opens and closes the valve quickly and has a flat nose to hold it open and close to max lift for as long as possible. That design can be hard on springs, and you might need a double spring for that."
Steely adds that there is a large overlap in pressure between single- and double-spring designs. The choice is up to the engine builder.
Heat"We've done extensive testing with spintron machines, and it is amazing how much heat a spring can generate on its own," says Bechtloff. "Besides the radiant heat an engine generates from the combustion process, the heat a spring generates internally can be very damaging to the metal."
When it comes to cooling springs, there is nothing better than a continuous flow of good ol' engine oil. On high-end, dry-sump systems, this is best accomplished with dedicated spray bars in the valve covers that direct a mist of oil at the springs. That isn't feasible-or normally legal-in lower classes that require wet-sump oiling systems, in which case the best thing to do is simply not restrict oil to the heads. Do whatever you can to limit the oil from dripping down onto the crankshaft, but do not limit the amount of oil that can get to the springs.
Synthetic oil is also a good idea. Although it doesn't pull heat from metal any better than mineral-based oil, synthetic lubricants do not break down as easily when subjected to heat. This means that in high-heat environments, it can do its job better, longer.
If you are required to run a stock-type valvetrain, another option is Crane Cams' Kool Nut. Designed as an oversized rocker arm nut, the Kool Nut acts as a heat sink and also directs oil from the pushrod onto the fulcrum of the rocker arm, which is an extremely high-temperature area.
Record Keeping"The strongest mind can't hold information like the weakest ink," Godbold says of monitoring your valvesprings' performance. He's talking about record keeping, and he's absolutely right that a simple notepad and ink pen can be among the most valuable tools at your disposal.