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Diamond 30803 - 5.8L Shelby Series Piston / Ring Kit -15.0cc Dish, 3.681" Bore

10.0:1 Compression - Supplied with AP Steel Ring Set - Designed for factory Plasma Liner
Pricing: $1,087.97

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Diamond's all new 5.8L Trinity Shelby Series Pistons feature a much taller compression height to bring the Piston closer to the deck. This drastically improves combustion efficiency and flame travel while allowing the rings to be spaced out for additional strength. These Pistons are designed to be used with the factory Plasma Transfer Wire-Arc liner.


  • 2618 Alloy Forging for High HP Applications
  • .320" Down Top Ring Land 
  • .151" Intake / .050" Exhaust Valve Reliefs 
  • Moly Coated Skirts
  • Premium 8620 Wrist Pins - H-13 Tool Steel Upgrade optional
  • Total Seal AP Steel Piston Ring Set - Napier 2nd Rings 

Compression Ratio: 10.0:1
Compression ratio calculated with 3.700" Bore / .036" Compressed Thickness


Part Number   30803
Piston Material   2618 Aluminum Alloy 
Fitment   Ford 5.8L Trinity - Factory Spray in Liner 
Piston Volume  -15.0cc  
Bore  3.681" 
Stroke  4.165"  
Rod Length  6.657" 
Compression Height  1.315" 
Wrist Pin Dimesions .866" x 2.500" x .180" Wall 
Wrist Pin Material  8620 Alloy
Optional Wrist Pin Dimensions  .866"x 2.500" x .200" Wall
Optional Wrist Pin Material  H-13 Tool Steel 
Included Piston Ring Set  09523681
Piston Ring Stack  1.2mm x 1.5mm x 3.0mm 
Piston Ring Specifications  AP Steel Top, Napier 2nd, 3 Piece Stainless Oil 

H-13 Wrist Pin upgrade suggested for applications over 800 HP 



Shipping Information

  • Item Requires Shipping
  • 14.0 lbs.
  • W28.0000” x H12.0000” x L6.0000”
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