LT1/LT4/LT5 BoostPrep STROKER Shortblock (Gen.V LT)


Bore: 4.070"

Stroke: 4.000"

Connecting Rod Length: 6.125"

Displacement: 6.8L / 416c.i.

Piston Volume: -20cc or -16cc dish with valve reliefs

Compression Ratio:

10.5:1 with 59cc(LT1 Heads with -20cc dish pistons)

10.2:1 with 65.5cc(LT4 heads with -16cc dish pistons)


Horsepower Rating: Up to 1400whp


Engine Block: New OEM LT1/4/5 Aluminum Block


1200whp option: Callies Compstar Stroker Crankshaft

1400whp option: Callies 8 Counter Weight Magnum Crankshaft

Pistons: Wiseco or Diamond Racing Forged Pistons

Connecting Rods: 

1200whp option: Callies Compstar H-Beam Connecting rods w/ ARP rod bolts

1400whp option: Callies Ultra Billet H-Beam Connecting rods w/ ARP rod bolts

Main Fasteners: ARP Main Studs

Main Bearings: King XP-Series Race Bearings

Rod Bearings: King XP-Series Race Bearings

Cam Bearings: Durabond one piece bearings


Cylinder Heads: Strictly Spec'd CNC Ported LT1 or optional LT4 Heads


LT1- 2.126" Hollow Stem Steel intake  / 1.590" Sodium Filled Steel exhaust 

LT4- 2.126" Titanium intake / 1.590" Sodium Filled Steel exhaust


Valve Springs: .660" Lift Dual Valve Springs w/ Titanium retainers

Camshaft: Application Specific Spec'd Camshaft

Timing Chain: Katech C5-R Timing Chain

Lifters: OE Replacement LS7 Lifters

Push Rods: 3/8 Diameter Chromoly Pushrods

Rocker Arms: New GM LT Rocker Arms w/ trunnion upgrade

Head Fasteners: ARP Head Studs

Head Gaskets: GM MLS Head Gaskets

Oil Pump: OEM GM Oil Pump


416 STROKER LT1/LT4/LT5 BoostPrep Longblock (Gen.V LT)