Review on PAC-1218 Valve Spring: GM LS-Series Compatibility, High Performance Ovate Beehive Spring (16 PCS) by Rudy Hilmy

These were installed with a new 212/218 .553/.553 camshaft and new ls7 hydraulic lifters. After setting it up and running 100 miles, the truck developed severe slippage and a terrible rattle. I removed the valve cover and found that the spring had snapped and may have bent the valve. I do not recommend this product at all and now I have to remove the cylinder head to check because the valve is difficult to move. Very disappointed in this product and can't believe I have to go through all that work and money all over again. Update: Picture of a broken spring and zero compression sensor after replacing the spring, rocker arm and pushrod with the originals. This company product is costing me hundreds more in cash and my own man-hours and I haven't heard anything. Update #2, this time another spring broke on the driver's side so I had to pull the head again to replace another bent valve. I will be pulling all the springs to replace with a BTR branded spring set. Once again PLEASE DO NOT BUY!