Upgraded valve springs to allow increased engine speed limit to 7000 rpm. Stiffer springs that increase the closing pressure on the valves to maintain control over the intake and exhaust valves (preventing “valve float”) at higher than stock boost pressure and engine speed. 27% higher seat pressure (56.6 lbs vs 44.5 lbs stock) and ~29% higher pressure at open (101.6 lbs vs 78.5 lbs stock). These are not too aggressive and should solve the float issue at boost pressures up to ~28+ psi at stock redline, or lower boost at higher redline). 16 springs total are required to replace the springs on all of the intake and exhaust valves.