Engine Builder's Specs
SHORT-BLOCK
Displacement: 374.2 ci
Bore x stroke: 4.125 x 3.500
Rod length: 5.4
Rod/stroke ratio: 1.54:1
Block deck height: Milled to 8.195
Piston compression height: 1.040
Piston deck height: 0.005
Piston volume: 13.3cc dome
Head-gasket compressed volume: 11 cc
Compression ratio: 14.50:1
Piston-to-wall clearance: 0.006
Main- and rod-bearing clearance: 0.0031
Rod side clearance: 0.012
Crankshaft thrust clearance: 0.007
Piston compression-ring endgap: 0.014
Piston oil-ring rail endgap: 0.022
Floating piston pin-to-rod: 0.002
Piston-to-head clearance: 0.056
Bobweight: 1310 g
Camshaft thrust: 0.005
Camshaft specs: See Cam Specs chart
CYLINDER HEADS
Valve size: 2.080/1.600
Combustion-chamber volume: 58 cc
Intake-port volume: 245 cc as ported
Max flow: 340.1/240.9 cfm @ 28in H2O
Exhaust/intake flow ratio: 70.8%
Valvespring od/id: 1.645/0.635
Valvespring seat pressure: 350 lbs @ 2.100
Valvespring open pressure: 950 lbs @ 1.200
Valvespring coil-bind height: 1.150
Piston-to-valve clearance: 0.020/0.060 at running lash
Spark plugs: NGK R5672-9, 0.055 gap
CRITICAL FASTENERS
Values are with ARP lube; those not listed are the same as production.
Ford Racing Grade 8 main bolts (11/42): 100 lb-ft
ARP head studs (11/42): Bottom hand-tight (dry)
ARP head stud nuts (11/42): 108 lb-ft
ARP Manley rod bolt (31/48): 50 lb-ft
Jesel rocker stand supports (71/416): 60 lb-ft
Jesel mini-shaft bolts (51/416): 25 lb-ft
All dimensions are in linear inches, except as noted.