Torque Specs

Torque Specs

Ford Barra Workshop Manual

Ford Barra Workshop Manual

WORKSHOP MANUAL PDF

Key Torque Specs

Cylinder Head Stud – 12.0mm

100 with Moly

135 NM with Moly

Cylinder Head Stud – 14.3mm

135-140 with Moly

187-190 NM with Moly

Camshaft Caps Saddles

10 with Loctite 222

13 NM with Loctite 222

Main cap bolts – without girdle

65 with Oil

88 NM with Oil

Main cap bolts – with girdle

75 with Oil

100 NM with Oil

Main cap studs – with girdle

75 with Oil

100 NM with Oil

STEEL Main caps  -
studs & girdle

100 with oil

135 NM with oil

Camshaft sprocket bolts – M10

55 with Loctite 222

72 Nm with Loctite 222

Camshaft sprocket bolts – M6

13 with Loctite 222

17 NM with Loctite 222

Camshaft sprocket bolts – M8

23 with Loctite 222

31 NM with Loctite 222

Steel conrods – ARP 3/8” bolts (Atomic rods <2023)

55 with Moly

72 NM with Moly

Steel conrods – CA635 3/8” bolts (2023 onwards)

60 with Moly

87 NM with Moly

Steel conrods – ARP 7/16” bolts

65 with Moly

87 NM with Moly

Alloy conrods – Carrillo 7/16” bolts

100 in a single movement with oil on threads

134 NM in a single movement with oiled threads

Harmonic balancer retaining bolt

100 with Silicone 250 on washer and keyway, moly on thread
then Loctite 222

135 NM with Silicone 250 on washer and keyway, moly on
thread, then Loctite 222

Sump cross bolts – M10

50 with Loctite 222

67 NM with Loctite 222

Sump to block bolts - M6

10 with Loctite 222

13 NM with Loctite 222

Timing pivot bolt – M18

19 with Loctite 222

25 NM with Loctite 222

D/Side pivot bolt - M8 flange nut

20 with Loctite 222

27 NM with Loctite 222

Oil pump pickup support brace – M8 crimp nut

15 with Loctite 222

20 NM with Loctite 222

Oil pump bolts

12 with Loctite 222

16 NM with Loctite 222

Oil pump pressure relief valve

33 with Loctite 222

45 NM with Loctite 222

Flywheel/flexplate bolts

70 with Moly under heads and Loctite 262 on threads

100 NM with Moly under heads and Loctite 262 on threads

Bearing Clearance Suggestions

All clearances are general suggestions and must be tailored to suit your parts, power goals, intended use, oil, quality of parts etc. Atomic is trying to share some information to those who need a starting point and is not responsible for any issues arising from the use of this information. If you are unsure please contact a professional engine builder for guidance.

Item | Desired clearance in inches

Conrod bearing – steel conrod .002” - .0022”

Conrod bearing – alloy conrod .002”

Conrod side clearance – steel conrod .008” minimum

Conrod side clearance – alloy conrod .018” minimum

Conrod small end – steel conrod .0005”

Conrod small end – alloy conrod .001”

Main bearings – vertical bearing clearance .003” - .0035”

Thrust – 180 or 360 degree .004” - .006”

Thrust – Torrington .004” - .005”

Piston rings – Top ring Steel .024“ minimum

Piston rings – Second Iron .022” minimum

Piston rings – Oil expander .005” maximum

Piston rings – Oil rails .018” minimum

Piston deck height variation – minimum .005”

Piston to bore clearance – Cast pistons NO grout .002” minimum

Piston to bore clearance – Forged pistons NO grout .0045” minimum

Piston to bore clearance – Forged pistons WITH grout .0055” minimum

Piston to valve clearance .060” minimum

Valvespring retainer to valvestem clearance .060” minimum

Lifter preload – hydraulic .020” minimum, .050" maximum

Tappet clearance – solids Refer cam manufacturers spec