Specifications for 4
1
⁄
8
” Bore Engines
Displacement
Bore
Stroke
Compression Ratio
111”
4
1
⁄
8
”
4
1
⁄
8
”
9.7:1
117”
4
1
⁄
8
”
4
3
⁄
8
”
10.2:1
124”
4
1
⁄
8
”
4
5
⁄
8
”
10.8:1
Cylinder Heads
Specification
Valve Guide in Head (tight)
.0015” - .003”
Valve Seat in Head (tight)
.005” - .0075”
Crankcase
Specification
Service Wear Limit
Timkin
®
Race in Case (tight)
.001” - .003”
less than .0025”
Pinion Race in Case (tight)
.001” - .003”
less than .0025”
Valves (Fit in Guide)
Specification
Service Wear Limit
Intake
.0012” - .0015”
.0025”
Exhaust
.0018” - .0023”
.0035”
Seat Width
.040” - .062”
Stem Protrusion
2.045” - 2.060”
2.080”
Flywheels
Specification
Service Wear Limit
Runout (Shaft at Flywheel)
.0005” - .001”
.003”
End Play
.001” - .005”
exceeds .005”
Pinion Bearing Fitment
.0004 - .001”
.002”
Rocker Arms
Specification
Service Wear Limit
Shaft Fit in Bushing (Loose)
.0007” - .0018”
.0035”
Bushing Fit in Rocker
Arm (Tight)
.002” - .004”
Connecting Rods
Specification
Service Wear Limit
Crankpin Bearing
Running Clearance
.001” - .0012”
.002”
Piston Pin Fitment in Red
.0005” - .001”
.002”
Connecting Rod Side-play
.015 - .035”
.040”
Hydraulic Lifters
Specification
Service Wear Limit
Lifter Fit in Guide (Loose)
.0006” - .0017”
.003”
Connecting Rods
Specification
S&S
®
Suggestions
Pinion Gear Nut
50 Ft.-Lbs
Loctite
®
272
Rocker Box Hardware
1
⁄
4
”
120 in.-Lbs
Loctite
®
243
Rocker Box Hardware
5
⁄
16
”
18 Ft.-Lbs
Loctite
®
243
Tappet Guide Fasteners
120 in.-Lbs
Loctite
®
243
Pushrod Locknuts
120 in.-Lbs
Cylinder Head Bolts
See Chart on Page 9
Crankcase Fasteners
1
⁄
4
”
120 in.-Lbs
Crankcase Fasteners
5
⁄
16
”
15 Ft.-Lbs
Gearcover Fasteners
120 in.-Lbs
Loctite
®
243
Intake Manifold-to-Head
16 Ft.-Lbs
Loctite
®
243
Intake Manifold-to-Carb
18 Ft.-Lbs
Loctite
®
243
Exhaust Flange-to-Head
60-80 in.-Lbs
Anti-seize
Tappet Screen Plug
120 in.-Lbs
Timing Hole Plug
120 in.-Lbs
Spark Plug
11-18 Ft.-Lbs
Anti-seize
Cylinder Studs
10 Ft.-Lbs
Loctite
®
262
Pistons
Specification
Service Wear Limit
Fit in cylinder
.002” - .0025”
.005”
End Gaps: Top Two
Compression
.017” - .025”
.028”
Oil Control Rails
.015 - .035”
.050”
Gearcase
Specification
Service Wear Limit
Breather Gear End-play
.005” - .015”
Breather Gear Running
Clearance
.0015” - .0025”
.004”
Camshaft in Bushing
.0007 - .002”
.003”
Camshaft End-play
.005” - .015”
Pinion Shaft in Bushing
.001” - .0025”
Bushing Fit in
Gearcase (Tight)
.002” - .004”
Oil Pump Shaft Clearance
.0007” - .0023
.0035”
20