Fits GM BB 396-502 exc 348 and 409, Ford 5.0L, SB 289-302-351W, Mopar 413 f body We are especially proud to

We are especially proud to introduce our own ultra-premium springs built from CrSi wire and featuring 530 lb/in front and 130 lb/in linear rates

Each valve features a one-piece forged titanium construction with superior grain flow to eliminate weak points and ensure long-term strength

allowing for a total of 361 possible valving combinations

After being self-locked in this manner

don't overlook this essential component

Fits GM BB 396-502 exc 348 and 409, Ford 5.0L, SB 289-302-351W, Mopar 413 f body We are especially proud toPROFORM Wedge Locking Header Bolts ELIMINATE the need to constantly re tighten collector bolts, and without the need for clips, pins, racing wire, chemicals or gunk. The secret is in the Wedge Locking Washer's super hardened external teeth that "bite" into the bottom of the bolt head and the top flange surface. Vibrations that normally cause other bolts to loosen, are blocked by the wedge locking action that uses tension, instead of friction to stay