What is a connecting rod?
A connecting rod is an engine component that transfers motion from the piston to the crankshaft and functions as a lever arm. Connecting rods are commonly made from cast aluminum alloy and are designed to withstand dynamic stresses from combustion and piston movement.
How does connecting rods work?
A Connecting rod is used to transfer reciprocating motion of piston into rotary motion of crankshaft.
This whole process is done by cylinder, piston, crankshaft and connecting rod. It has two ends - Small
End and Big End. The small end is connected to piston with piston pin and the big end is hold by
crankshaft through crankpin. The small end may have a solid or split eye but the big end is always
split. The split shoulder end is assembled with a cap by clamping bolt.
The oil hole is generally
drilled through shank to allow flow of lubricating oil from big end to small end. The oil comes on the
big end through the crankshaft from force feed lubrication speed and goes to piston pin and piston
through small end. The connecting rod in operation is subjected to combined axial and bending stresses.
The combustion gas pressure and inertia forces produce axial stresses while bending stresses are
produced due to centrifugal effects. To minimise these inertia load a connecting rod should be as light
in weight as possible.
How to Choose the right connecting rods?
Connecting rods are placed under more stress than any other component in the engine. Selecting the
strongest rod for a performance target is absolutely essential. As we all know, if a connecting rod
fails, the engine can be turned to junk in a fraction of a second. So choose wisely and do not select
inexpensive rods.
How to get the right con-rods for your engine? It's not as simple as it sounds. What
con-rods to choose is very important when building your engine. Con-rods not only affect whether best
fit your engine or not, they also play a huge part in your engine performance and longevity. And there
are some factors you have to consider when choosing your con-rods. I will mention two factors in the
article.
Firstly, the style or the type of con-rods that are available to fit your engine, I-Beam or H-Beam?
The I-Beam Connecting Rods have a sort of concave side that runs the length of the rod and has raised
edges. If you cut that in half, you would find that the rods look like the letter “ I ”. Maybe that's
why called I-Beam Connecting Rods.
The I-Beam Connecting Rods are lighter in weight, which makes them be
the preferred choice for higher revving and RPM applications. They can save weight and provide extra
clearance with less strength. So the I-Beam design is often used on stock connecting rods cause the
combination of lighter weight and strength.
To the H-Beam Connecting Rods, which have larger flat sides that run the length of the rod with a thin
center selection in the middle. Same as I-Beam Connecting Rods, if you cut that in half, you will find a
letter " H ".
The H-Beam Connecting Rods are a little bit heavier, stiffer, more rigid and stronger than I-Beam, so
they are the priority selection for high horsepower and high cylinder pressures. They can better
distribute and handle the higher compressive loads which placed on them.
“H-beam is a stronger design when bending stress is considered,” Davis said. “H-beam rods are more
difficult to machine, so they are often more expensive. I-beam rods are easier to produce and can
sometimes be lighter than H-beams. All other variables being equal, H-beam rods are the strongest
design.”
Whether you choose H-beam or I-beam, you should also consider the other factors.
Secondly, the con-rods material. Steel or Aluminum?
Steel rods are made with many types by manufacturers, like cast-steel, forged steel, and billet steel.
Most aftermarket steel con-rods are made from forged steel, and there are different styles of forged
steel on basis of the material grade, for more highly modified competition applications, the majority of
manufacturers, including us ( MaXpeedingrods ), use the 4340 steel.
The steel connecting rods are suitable for most application cause the special material. Steel won't
stretch or fatigue easily.
The aluminum rods are absolutely a lighter weight to choose for high RPM, higher and faster revving,
reducing vibration and stress on the crankshaft, which makes them very popular for racers, while they
are less stronger than the steel and they have a more limited longevity depending on how they are used.
The steel con-rods are less prone to stretch and fatigue than aluminum as easily cause the heavier
weight.
Many racers want their con-rods last as long as possible, so the steel con-rods are the preferred and
economical choice, but if you are a racer and can afford a new set of rods frequently, aluminum rod is
also a good choice.
Why buy connecting rods at MaXpeedingRods?
MaXpeedingRods has been engaged in the research of overseas racing products and culture for decades. If
you are looking for connecting rods, you have landed at the right place. On the basis of your vehicle
make and model, you can choose from a plethora of automotive maintenance and accessories. MaXpeedingRods
offers a seamless online shopping experience and the streamlined e-commerce interface makes it easy for
you to find just the connecting rods you want.
MaXpeedingRods offers a variety of connecting rods in both Sport performance and Street performance.
• Forged 4340 aerospace steel
• Unique titanium plating process
• With Standard ARP L19 bolts
• Professional design and precision machining center assembly line manufacturing
• US SUNENEN honing machine professional honing
• 100% X - ray, ultrasonic, magnetic particle inspection
• Multi-stage heat treatment and professional shot peening to eliminate stress
• Single connecting rod can bear more than 250 pieces of single weight error of each set less than
+/-0.2g
• Forged 4340 aerospace steel
• With Standard ARP 2000 bolts (Upgradable ARP L19 or ARP 625+ bolt )
• Professional design and precision machining center assembly line manufacturing
• US SUNENEN honing machine professional honing
• 100% X - ray, ultrasonic, magnetic particle inspection
• Multi-stage heat treatment and professional shot peening to eliminate stress
• Single connecting rod can bear more than 200 pieces of single weight error of each set less than
+/-0.5g
What are the symptoms of failure connecting rod in your vehicle?
A connecting rod needs to be strong and durable for the engine to survive. If it is too weak to handle
the load of the combustion, then all the pressure will wear it down and bend it out of shape. This would
be a very bad thing for the engine because there would be no more intake strokes, exhaust strokes,
compression strokes, or power strokes.
As for the driver, they will be able to notice when this occurs because there will be some very
noticeable symptoms present. Below are the top 4 symptoms of connecting rod failure that could happen to
you.
If you have a bad or failing connecting rod, then it may cause your engine to consume too much oil. Because of this, you may find that your engine always has a low level of oil. Either that or your existing oil will need to be changed more often than usual.
2. Engine Knocking Sounds.When your engine is turned on and running, you may hear a knocking sound coming from it. This will be a repeated knocking sound that gets faster as your engine speed increases. The sounds may go away after a short while, once your oil has a chance to circulate through the engine components and lubricate them.
3. Reduced Oil Pressure.A bad connecting rod could have devastating effects on your engine's oil pressure. There may be an oil pressure gauge on your engine which will tell you when it has low oil pressure. You could have a warning light on your dashboard that will tell you as well. If you have low oil pressure, then it means oil cannot circulate properly through the engine. This might lead to an overheated engine if the problem is not resolved quickly.
4. Bent or Damaged Rod.If you suspect that you have a bent or damaged connecting rod, based on the other symptoms which may be present, then you need to visually inspect the rod yourself to see what its condition is. This would require your engine to be disassembled, which is a job that only a mechanic should do.
How to install connecting rods in a car?
Have you ever wanted to know how to install a Connecting Rods, but the task seems too daunting. If you buy connecting rods from MaXpeedingRods, be sure to read the installation instructions carefully.
1. All conrods must be completely cleaned with suitable cleaner and dry compressed air before loosening
the fasteners and removing the caps.
2. There is pre-lasered numbers on each rod big end side, so you can reassemble the correct cap to
matching rod body easily and accurately. Do not swap any conrads and caps.
3. Disassemble the conrods, carefully clean all conrods area and attaching hardware surfaces.
4. To make sure proper installation, the Rod bearing clearance should be controlled according to your
application manual and checked accurately by dial bore gauge(Plastic gage is not recommended), the
clearance is different by individual application.
5. Assemble the cap on the conrod by hand and Align dowels register with the counter bores.
6. Gently tap canrod cap by wood or rubber hammer until it's fully seated. Don't use any metal or hard
object to tap the cap.
7. Clean out debris and grease residue on conrods before put on fasteners lubrication.
8. Must use Moly bolt lube to lubricate fastener threads and under head clamping face. ARP fasteners
lubrication is highly recommended.
9. Tighten the fastener with accurate torque according to below ARP Conrods fasteners torque table. Over
torque may damage the conrods or even engine.