MHP 4.310 - 4.315" Total Seal Ring Set - Gas Ported Top Rings - MHP-R4310A
Moonshine Horsepower Total Seal Ring Set – Part # MHP-R4310A
This is the exact ring pack we run on every Moonshine Horsepower M8 Stroker 135 pistons and Moonshine Horsepower 131 builds, including our famous Ass Eater setup. Spec’d by us and built by Total Seal, the MHP-R4310A combines thin, low-friction rings with modern gas-porting and coating technology for maximum sealing, reduced blow-by, and real durability in high-output Milwaukee-Eight engines.
Why This Ring Set Works in High-Performance Builds
Gas-Ported Top Rings
Instead of drilling gas ports in the piston (which weakens the top land, especially near valve reliefs), these 0.9 mm top rings have the ports built into the ring itself. Combustion pressure flows through the ports and loads the ring from behind, pushing it firmly against the cylinder wall exactly when cylinder pressure is highest.
Benefits include:
- Dramatically improved ring-to-wall seal under load
- More even pressure distribution (more ports than typical piston gas-porting)
- Self-cleaning action because the ring rotates — ports don’t carbon up like fixed piston ports
- Less blow-by → cleaner oil, longer oil life, and more power transferred to the crank
- Stronger piston because no ports are drilled in the top land
They use Total Seal’s Advanced Profile (AP) process for tighter tolerances and better sealing than conventional rings, and are finished with the C-33 PVD Chrome Nitride (CrN) face coating. This aerospace-grade coating delivers excellent wear resistance and low friction while seating more easily than traditional chrome.
0.9 mm Ductile Iron Napier Second Rings
The Napier profile features a sharp-edge design with positive torsional twist. It scrapes oil more effectively than a conventional second ring while reducing parasitic friction. Combined with the thin 0.9 mm width, these second rings help control oil without adding unnecessary drag — important when you’re chasing every horsepower in a stroker.
3.0 mm 3-Piece Oil Control Rings (9–12 lb tension)
Modern oil-ring tension in the 9–12 lb range provides solid oil control without the high parasitic drag of older 15–20+ lb rings. Lower tension means less friction and heat, while the 3-piece design still keeps oil where it belongs in a high-output engine.
Key Advantages for M8 Stroker / High-Horsepower Applications
- Thin 0.9 mm top and second rings reduce mass and friction compared to thicker traditional rings → more usable power and better high-RPM behavior
- Superior sealing under high cylinder pressure (naturally aspirated or with power adders)
- Reduced blow-by keeps combustion gases out of the crankcase and protects oil
- Durable materials and coatings built for sustained high-output use
- Proven combination we trust in our own Moonshine Horsepower Stroker 135 engines and all of our Moonshine Horsepower 131 builds, including the Ass Eater
- Designed as a matched set for the MHP M8 Stroker 135 pistons and used across our 131 lineup
Specifications
This is not a generic ring pack. It is the combination we use when we want maximum seal, minimum friction, and long-term reliability in high-performance M8 stroker and 131 builds. Proper cylinder finish (we recommend our CNC Rottler hone process) is critical to getting the full benefit of these rings.