Exhaust Header Gaskets For a tight seal, don't forget the gaskets for your Schoenfeld headers. They offer exhaust header gaskets made with steel and stainless steel core laminate to provide stability, maximum torque retention, and excellent heat resistance. Schoenfeld has several port styles available to match your needs. You don't crack under the pressures of racing, and your gaskets shouldn't either. Steel Core Laminate, D Port, Chevy, Small Block, Each Port Height (in):1.520 in. Port Width (in):1.480 in. Thickness (in):0.062 in.