the solid bridge is combined with a full body length reinforcement
rib to give this caliper the highest resistance to deflection and
separation under load of any Superlite style caliper available.
Four high strength steel bridge bolts and a fifth center bridge
bolt further add to the superior clamping efficiency while providing
easy access to the 7420 style pads.
All SL4 series calipers use a big differential bore four-piston
design. The 1.88" / 1.75" piston sizes provide the largest
effective piston clamping area of any model in the Superlie series.
The differential bore pattern uses the pressure variance between
the bore sizes to compensate for the natural temperature changes
across the face of the pad and the natural tendencies for the pad
to "self load" on the leading edge. The split balance
of the pad loading promotes even pad wear in the higher temperature
applications. Standard SL4 models use one piece stainless
steel pistons for their low heat transfer properties and their high
resistance to corrosion. For the ultimate protection in extreme
sustained high heat competition, SL4/ST models are equipped
with Wilwood's exclusive Thermlock®
pistons. This multi-part piston assembly provides a highly effective
thermal barrier that reduces heat transfer from the pads to the
fluid, seals, and caliper body by as much as 30%. Seal life and
fluid performance is increased proportionately. High temperature
square faced seals provide the largest possible sealing surface
area with controlled piston retraction on release.
Every SL4 and SL4/ST caliper incorporates new and
adapted performance features from other Wilwood designs. Each caliper
is equipped with replaceable SRS stainless steel bridge wear plates.
SRS plates eliminate the bridge wear caused by pad gouging to extend
the service life of the caliper. The spring-loaded action of the
SRS plates eliminates pad rattle and dampens the vibration harmonics
that contribute to pad squeal. The bodies are machined with recesses
to protect the fluid crossover tubes and bleed screws. The fluid
tubes are dampen mounted and two piece bleed screw assemblies assure
reliability in harsh conditions and round out the total performance
package. The full range of PolyMatrix compounds is available in
the 7420 type pads to match the brake response and heat range of
any competition application. |
