REMFLEX Chev Big Block 454 ZZ502 Exhaust Gaskets # REM2029REMFLEX Chev Big Block 454 ZZ502 Exhaust Gaskets # REM2029 Exhaust Header and Manifold Gaskets, Rectangular Port, Graphite, Fits Old style GM Performance ZZ502 Heads, Chevy, 7. 4L, 8. 2L, Pair Port Style: Rectangular Gasket Material: Graphite Port Height (in.): 1. 750 Port Width (in.): 1. 875 Quantity: Sold as a pair. Notes: Fits old style GM Performance ZZ502 heads. Suggested torque of 20 25 lbs. ft. Remflex Exhaust Header Gasket Sets Remflex exhaust