Torque Factory Spec. BC (Crower) Valve Springs and Titanium Retainers Audi B5 S4 - A6 - Allroad with 2.7t - 2.8 Heads Retainer Kit

Springs are from PAC Racing and are wound from high grade, super clean, chrome silicone alloy and the retainers are CNC machined from 6AL4V titanium round stock.

Since Torque Factory specializes in the venerable Audi 2.7 engine the valve pressures were tested at the most popular cam lift profiles for the S4, RS4 and 2.8. 

●      Lighter weight titanium retainers lowers the valve train weight changing direction.  This allows higher limits to valve control at relative spring rates.

●      Higher spring rates and lower valve train weight allows the RPM limit to be extended to 8200+.

●      Higher closed seat pressure for consistent valve sealing at high boost pressures.

Intake:

Single spring

Closed seat pressure @ 1.450” installed height 72 lbs / 140% over original.

Open pressure at .301” lift (OE S4 camshaft) 115 lbs / 44% over original.

Open pressure at .341” lift (2.8 camshaft) 124 lbs / 38% over original.

Exhaust:

Single spring

Closed seat pressure @ 1.300” installed height 72 lbs / 16% over original.

Open pressure at .410” lift (S4, RS4 and 2.8 camshaft) 204 lbs / 54% over original.

Replacement spring options are limited and costly for the 2.7 and this option packs comparable performance for a reasonable amount.

We hope you consider Torque Factory.

These valves and retainers replace VAG part numbers:

Intake spring: 058109633

Exhaust spring: 078109623E

Intake retainer: 058109641D

Exhaust retainer: 058109641E