ICON Premium Forged Big Block Chrysler 400 "B" 451ci / 511ci Pistons Flat Top 4.375" Bore

Name: ICON Premium Forged Big Block Chrysler 400 "B" 451ci / 511ci Pistons Flat Top 4.375" Bore
Brand: UNITED ENGINE MACHINE
SKU: 648-IC823.033
Price: 793.42 USD
Availability: InStock

^$793⁴²

Ships on 09/14/2026

Lowest Price Guarantee

Chrysler "B" 451ci / 511ci

Flat Top Pistons

451ci Use w/ 6.768" Connecting Rods & 3.750" Crank Stroke

511ci Use w/ 6.535" Connecting Rods & 4.250" Crank Stroke

Big Block Chrysler "B" 451ci / 511ci Forged Pistons

Flat Top

4.375" Bore (+.033")

451ci - 6.768" Rod & 3.750" Stroke; C/R 11.3/75cc; 11.0/78cc; 10.0/88cc

511ci - 6.535" Rod & 4.250" Stroke; C/R 12.7/75cc; 12.3/78cc; 11.2/88cc

8/pkg.

Technical Notes:

For use with 400 "B" blocks
Stock standard 400 cylinder bore is 4.342" with 3.380" crankshaft stroke
4.375" Bore + 3.750 Stroke = 451ci
4.375" Bore + 4.250 Stroke = 511ci

Technical Specs:

Alloy: Premium High Ductility 2618
Bore: 4.375"
Crankshaft Stroke: 3.750"
Connecting Rod Length: 6.768"
Deck Height: 9.980" (RB)
Compression Height: 1.322"
Pin Size: 0.9900' x 3.000"
Pin Location: Centered
Flat Top: 2 Valve Reliefs
Effective Head Volume: 4.5cc
Intake Valve Relief: 0.215" Depth / 2.300" Diameter
Exhaust Valve Relief: 0.199" Depth / 1.880" Diameter
Top Landing Height: 0.250"
Ring Grooves: 1/16" Top; 1/16" Middle; 3/16" Bottom
Gram Weight: 542/158
451ci Compression Ratio: 11.3:1 w/75cc Heads; 11.0:1 w/78cc Heads; 10.0:1 w/88cc
511ci Compression Ratio: 12.7:1 w/75cc Heads; 12.3:1 w/78cc Heads; 11.2:1 w/88cc