here's a new china plug i have found,
OHM/GOD spark plugs ( Oh-my-god's? )
and the specifications sheet,
besides having bad translation/spelling, i think they got the A and B around the wrong way too!
Cross reference NGK number::
C7HSA
Suit for:
C50 PC50K
Product Description
Technology:
1. Multi-ribs of insulator eliminate flashover.
2. Insulator made of 95% pure alumina, strong resistant to heat shock, great mechanic and electric features, super insulation.
3. Nickel plated housing prevents oxidation and corrosion, heat crimping process ensures absolute gas-tight fit.
4. Inner sealing with conductivity glass ensures a fine conductivity and sealing.
5. Multi-layer gaskets are elastically strong, and reliable in sealing.
6. Copper core electrode prevents oxidation and corrosion, good electric and heat conductivity, prolongs spark plug service life
Insulator
Class A
Alumina Content 87%-90%
Class B Alumina Content 95%,Reliable Insulation,Heat Bearing And Mechanical Performance
Housing
A Made By Meter Lathe,Low Precision,Low Antioxidation
B Shape By Cold Extruding,High Precision,High Antioxidation
Center Electrode Low Nickel Nontent Cheap Raw Material CNY 25-28/KG
NiCrsi Alloy High Raw Material
A CNY>250/KG,High Ablative Resistance,Long Service Life Bolt, A3 Steel As Material,No Tensile Test
B Ml10 Riveting Screw Steel ,Pass Tensile Test
Printing Overglaze Color, Underglaze Color Smooth Surface Durable Printing
Gournd Electrode
A Inferior Material Quanlity Magno Alloy,Abative Resistance, sealant, Aluminum Powder Glass,Low Thermostability
B Copper Powder Conductive Galss,High Thermostability
inner seal
Bolt Part
A Heating,Low Combination Between Sealant,Low Seal Performance
B Heating combination by sintering furnace,stable quality control,high seal performance.
Housing Carving, Twist Carving, Rolling carving,clear and balance carving
A Insulator Capacity no test normally
B Pass 25-35KV high voltage test,high insulation perfomance
Whole Assembly
A Poor quality stability
B Large current hot state seal,high seal performance
Appearance
A Rough,rolling plate rough screw,sintering scar
B Nice ,hanging palte clear screw,nitrogen protection no scar left