Supertech Valve Spring and Titanium Retainer Kit for 2003-2008 Audi S4 4.2L 40v V8 Engines
Set of 24 Single Valve Springs, 16 Dual Valve Springs, 40 Titanium Retainers and 16 Seats
SPRK-AUDI40-V8
Type: Intake Single Spring
Outer Spring: OD 20.60mm - ID 14.40mm
Inner Spring: None
Press.Seat Intake: 56lbs @ 36.60mm
Max Lift Intake: 13.60mm
Coil Bind: 23.00mm
Rate: 6.70mm
Retainer: RET-AU5VI/T2 (24)
Spring: SPR-A2095 (24)
Type: Exhaust Dual Spring
Outer Spring: OD 29.10mm - ID 21.90mm
Inner Spring: OD 20.50mm - 15.50mm
Press.Seat Exhaust: 75lbs @ 33.70mm
Max Lift Exhaust: 14.20mm
Coil Bind: 19.50mm
Rate: 10.00mm
Retainer: RET-AU5VE/T4 (16)
Spring: SPR-H1002D/AU (16)
Seat: SEAT-H1000 (16)
Our valve springs are computer designed to ensure that wire stress levels do not overpass the limits of stress defined in the diagrams of fatigue. We also utilize computer software that allows us to ensure that the harmonics are under control. All Supertech valve springs are made with premium super clean Chrome Silicon Vanadium Steel alloy for higher performance & durability at high rpms. Using high quality steel alloy also provides the added benefit of better structural memory for all of our springs, giving your performance racing engine a serious competitive advantage.
Supertech retainers are manufactured with high quality military certified Titanium alloy, and are CNC machined for a tight fit. Our high quality retainers are among the best in the industry.