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Introduction of 144 mm H-beam Steel Forged 4340 Conrods Connecting Rods Billet Racing Crankshaft
The connecting rod connects the piston and the crankshaft, and
transmits the force on the piston to the crankshaft, converting the
reciprocating motion of the piston into the rotational motion of
the crankshaft.
The connecting rod group is composed of connecting rod body,
connecting rod big end cap, connecting rod small end bushing,
connecting rod big end bearing bush and connecting rod bolts (or
screws). The connecting rod group is subjected to the gas force
from the piston pin, its own swing and the reciprocating inertial
force of the piston group. The magnitude and direction of these
forces change periodically. Therefore, the connecting rod is
subjected to alternating loads such as compression and tension. The
connecting rod must have sufficient fatigue strength and structural
rigidity. Insufficient fatigue strength will often cause the
connecting rod body or connecting rod bolt to break, resulting in a
major accident of damage to the whole machine. If the stiffness is
insufficient, it will cause bending deformation of the rod body and
out-of-round deformation of the big end of the connecting rod,
resulting in eccentric wear of the piston, cylinder, bearing and
crank pin, etc.
Structure and composition
The connecting rod body consists of three parts, the part connected
with the piston pin is called the small end of the connecting rod;
the part connected with the crankshaft is called the big end of the
connecting rod, and the part connecting the small end and the big
end is called the connecting rod body.
The small end of the connecting rod is mostly a thin-walled annular
structure. In order to reduce the wear between the connecting rod
and the piston pin, a thin-walled bronze bushing is pressed into
the small end hole. Drill or mill grooves in the small head and
bushing to allow splashing oil to enter the mating surfaces of the
lubricating bushing and piston pin.
The connecting rod shaft is a long rod, and it is also subjected to
large forces during work. In order to prevent it from bending and
deforming, the rod body must have sufficient rigidity. For this
reason, most of the connecting rod shafts of vehicle engines use
I-shaped sections, which can minimize the mass with sufficient
rigidity and strength, and H-shaped sections are used in
high-strengthened engines. Some engines use the small end of the
connecting rod to spray oil to cool the piston, and a through hole
must be drilled in the longitudinal direction of the rod body. In
order to avoid stress concentration, the connection between the
connecting rod body and the small end and the big end adopts a
smooth transition of large arc.
In order to reduce the vibration of the engine, the quality
difference of each cylinder connecting rod must be limited to the
minimum range. When assembling the engine in the factory, it is
generally grouped according to the mass of the large and small ends
of the connecting rod in grams. Group connecting rod. 144 mm H-beam
Steel Forged 4340 Conrods Connecting Rods Billet Racing Crankshaft
On the V-type engine, the corresponding cylinders of the left and
right rows share a crank pin, and the connecting rods have three
types: parallel connecting rods, fork connecting rods and main and
auxiliary connecting rods.
main form of damage of 144 mm H-beam Steel Forged 4340 Conrods
Connecting Rods Billet Racing Crankshaft
The main damage forms of connecting rods are fatigue fracture and
excessive deformation. Usually fatigue fractures are located in
three high stress areas on the connecting rod. The working
conditions of the connecting rod require the connecting rod to have
high strength and fatigue resistance; it also requires sufficient
rigidity and toughness. In the traditional connecting rod
processing technology, the materials generally use quenched and
tempered steel such as 45 steel, 40Cr or 40MnB, which have higher
hardness. Therefore, the new connecting rod materials produced by
German automobile companies such as C70S6 high carbon microalloy
non-quenched and tempered steel, SPLITASCO series Forged steel,
FRACTIM forged steel and S53CV-FS forged steel, etc. (the above are
all German din standards). Although alloy steel has high strength,
it is very sensitive to stress concentration. Therefore, strict
requirements are required in the shape of the connecting rod,
excessive fillet, etc., and attention should be paid to the surface
processing quality to improve the fatigue strength, otherwise the
application of high-strength alloy steel will not achieve the
desired effect.
AD Racing H-Beam Forged Connecting Rods For Toyota 2TG 2TC 3TC Engine Conrod Con Rods | |
Material | Forged 4340 Steel |
Copper bush Material | QAL10-3-1.5 |
Quantity | 1 Set of 4 Pieces |
Connecting Rod Finish | Shot-peened |
Weight Matched Set | +/- 1gram in set |
Dimensions | |
Center to Center Length | 123.20mm |
Big End Bore Diameter | 51.00mm |
Big End Width | 25.53mm |
Small End Bore Diameter | 22.00mm |
Small End Width | 21.82mm |
Bolts size | 3/8" |