Tomei Powered FORGED CONROD BOLTS - Manual (Page 4)

CAUTION
■ This product is designed for competition used ONLY. Not to be used on public roads.
■ The original safety standards of the vehicle will change, which will make it illegal to be used on public roads.
■ This product is to be fitted by an experienced professional in a fully equipped workshop.
■ This product is to be fitted with the correct tools, protective & safety equipment. Failure to do so can
lead to possible work hazards.
■ Refer to the vehicles original workshop service manual when disassembling the engine.
■ This product was specifically designed to be application specific. This is not a universal product. If
installed on any other vehicles/engines, this product may sustain damage and/or cause engine failure.
■ Designed specifically for performance use. All other parts will need to be checked during assembly to
ensure that everything is in excellent condition. If not, you run the risk of engine failure when used at high
engine speeds & power outputs. Meticulous attention to detail & precision assembly is a must for maximum
longevity & durability. Since this is a vital component of the engine, any mistakes made during assembly, will
cause terminal engine failure.
■ This product is to be installed when the engine and engine bay is cold.
■ Tighten each bolt with the torque specified with a torque wrench. If the bolt(s) loosens, damage to the
engine may result. Additional problems may arise if the bolts are not tightened to the specified torque specs.
■ Use an Angle Wrench to carefully measure the correct tightening angle. It is not possible to use another torque
method. When the correct axial tension tightening is not set, problems can arise later from it.
If problems arise later, it can lead to severe damages to the engine.
Approximately 80-90% of the torque applied
to the bolt it lost during friction, during surface
contact with the thread face and surface
[Change in axial tension according to difference of friction of surface]
μ＝0.08 μ＝0.12 μ＝0.20
g)
4
contact with the thread face and surface.
The remaining 10-20% can only then is
measured via the axial force. Accuracy is
vital to maximize the bolts longevity and
design purpose.
Frictional properties
0.08 (Small) 0.40 (Large)
・Surface-roughness ・Surface-roughness
small dice large dice
・Good Lubrication ・Poor Lubrication
【Influence due to tightening axial tension shortage】
・Defective bearings can lead to metal burns in the Engine. ・The noise is from excessive bearing clearance.
・A decrease in tightening axial tension, loosening will cause engine failure.
[Engine scorch by defective hit of metal]
・Engine failure due to metal defects. ・Engine failure due to inappropriate bearing clearance.
μ＝0.08 μ＝0.12 μ＝0.20
μ＝0.30
μ＝0.40
Clam
pi
ng
F
o
rce
(kg)
Torque (kgm)
4