}
Application: 1985-95 32-Valve Porsche® 928
These beehive springs are wound from super clean ovate valve spring wire and are both heat treated and shot-peened. The ovate wire allows for more travel to coil bind and is also thicker on the x axis of the spring giving it greater strength and fatigue resistance.
The design of a beehive spring combines the light weight of a single spring with better harmonic control than a dual spring. Since the beehive changes diameters from the top of the spring to the bottom, the natural frequencies also change with the diameters so the spring is not affected by harmonics like a single spring. The interference-fit center coil meant to dampen the harmonics on dual springs is also eliminated, as is all the heat and valve train stresses it created.
In addition, a beehive has a very small top coil, making the spring retainer much smaller and lighter for less moving mass than a straight wound spring. Consider that the intake valve opens and closes 50 times a second at 6,000 rpm, and you can appreciate how much a reduction in valve train mass can be!
The result is less heat, load and stress on the entire valve train, plus greater fatigue resistance and durability. Race tested, but a significant valve train improvement for non-race engines as well.
Two Sets Available: Chose the High-Rev spring set for naturally-aspirated motors planning to spin up to 8000 rpm. The High-Boost spring set is the right choice for supercharged engines running big boost - up to 20 psi.
Intake Closed Seat Pressure |
Pressure @ Intake Open |
Exhaust Closed Seat Pressure |
Pressure @ Exhaust Open |
Will Bind At |
|
---|---|---|---|---|---|
Stock 32v 928 Spring Set |
85 lbs | 195 lbs @ .354" lift OEM 928 S4 Cam |
78 lbs | 180 Lbs @ .313" lift OEM 928 S4 Cam |
.410" lift |
High Rev Beehive Spring Set |
100 lbs | 240 lbs @ .430" lift 928MS 32vR3 Cam |
100 lbs | 227 lbs @ .398" lift 928MS 32vR3 Cam |
.516" lift |
High Boost Beehive Spring Set |
115 lbs | 248 lbs @ .412" lift 928MS 32vR4 Cam |
115 lbs | 247 lbs @ .398" lift 928MS 32vR4 Cam |
.516" lift |