Mahle PR98MS-12-1 98mm Porsche Piston Ring Set 1.2/1.2/3.0mm 911 3.0L 3.2L 6cyl

Vehicle Fitment

• 1978-1983 Porsche 911 SC (3.0L Flat-6, Air-Cooled, SOHC, 98mm bore - CIS/Carb variants)
• 1984-1989 Porsche 911 Carrera (3.2L Flat-6, Air-Cooled, SOHC, 98mm bore - Carb, CIS, and Motronic variants)
• Compatible with Mahle Motorsport piston/cylinder sets PS98-014 and PS98-015 using 98mm bore
• Also fits any Porsche 911 flat-six engine build using 98mm bore pistons with 1.2/1.2/3.0mm ring grooves

Fitment Notes

• This is a single-cylinder ring set (1 ring set for 1 cylinder) - 6 sets required for a complete flat-six engine
• For the complete 6-cylinder ring set, see Mahle PR98MS-12 (sold as 6 sets)
• Ring pack: 1.2mm top / 1.2mm second / 3.0mm oil - file-fit; ring end gaps must be checked and set to spec before installation
• Designed for use with Mahle PS98-014 and PS98-015 piston/cylinder kits; verify piston ring groove dimensions before ordering if using third-party pistons
• Does not fit early Porsche 911 engines using 92mm, 84mm, or 90mm bores - confirm bore size before ordering
• Does not fit Porsche 964, 993, or water-cooled 996/997 platforms without confirming bore and ring groove dimensions

Features

• 1.2/1.2/3.0mm file-fit ring pack engineered specifically for 98mm Porsche flat-six performance applications
• Matched to Mahle's PS98-014/PS98-015 piston geometry and groove dimensions for precise ring-to-groove side clearances
• File-fit design allows ring end gaps to be set to specification for the builder's specific bore, stroke, and intended use
• Mahle Motorsport ring sets used across Porsche OEM and aftermarket high-performance builds worldwide
• Individual cylinder set allows selective replacement of worn rings on a single cylinder without purchasing a full 6-cylinder set
• Engineered for naturally aspirated, mild power-adder, and race applications on the air-cooled 911 flat-six platform

Specifications

• Bore Size: 98.00 mm
• Top Compression Ring Thickness: 1.2 mm - File-Fit
• Second Compression Ring Thickness: 1.2 mm - File-Fit
• Oil Ring Width: 3.0 mm - File-Fit
• Engine Type: Porsche Flat-6 (6-Cylinder, Air-Cooled, SOHC)
• Compatible Piston Kits: Mahle PS98-014, PS98-015
• Quantity: 1 set (1 complete ring set for 1 cylinder)
• 6 sets required for complete flat-six engine

Included Components

• 1x Top Compression Ring (1.2mm, file-fit)
• 1x Second Compression Ring (1.2mm, file-fit)
• 1x Oil Ring Assembly (3.0mm, file-fit)

Product Description

The Mahle PR98MS-12-1 is a single-cylinder replacement piston ring set for the Porsche 911 flat-six engine at 98mm bore, featuring a 1.2/1.2/3.0mm file-fit ring pack. It is the individual-cylinder equivalent of the PR98MS-12 six-cylinder set, allowing builders to replace rings on a single cylinder without purchasing a full engine set. This ring set is the correct replacement for Mahle's PS98-014 and PS98-015 piston and cylinder kits, covering 1978-1983 Porsche 911 SC (3.0L) and 1984-1989 911 Carrera (3.2L) applications using 98mm bore pistons with 1.2/1.2/3.0mm ring groove dimensions.

All three rings are file-fit - ring end gaps must be checked and set to specification for your specific bore, intended use, and fuel type before installation. Six sets are required to service a complete flat-six engine. For a full 6-cylinder ring set, see Mahle PR98MS-12. Always confirm piston ring groove dimensions before ordering if using third-party pistons, as groove dimensions vary across different 98mm piston designs. Compression ratio at 1mm deck clearance is application-specific and varies depending on the stroke and piston crown configuration used.