For high compression and elevated boost turbocharged engines, we recommend applying a set of quality machined Ni-Resist Rings. These rings are intended to provide a high integrity, interlocking seal between the cylinders and heads. The TurboKraft Ni-Resist Ring Set includes a set of 6 CNC machined billet stainless steel rings built to exacting tolerances. One of the original origins on Porsche engines dates back to the Porsche 935 race cars. These were also referred to as Flame Ring, Le Mans Ring and 935 Head Rings. Application will require the cylinders and heads to have a specially machined groove. Learn More