Pricey but very high quality. Used on record breaking drag cars these Beehive valve springs with lightweight titanium retainers are for use with billet cams. 80 seat pounds and 240 pounds @.500 max lift. To be used with stainless valves and roller rockers. Safe for 9500+ rpm

NOTE*** never use performance valve springs with stock valves. Stock valve failure is common. Always run a clearance of .060’’ between max lift and coil bind. Never use aluminum retainers, the aluminum retainers wear, create aluminum dust in the engine and in some cases the locks can pull through the retainer and drop a valve. This results in catastrophic failure of the engine. Especially for a high hour boat engine you want piece of mind.