CP Pistons include many great features off the shelf that many other piston manufactures leave for custom pistons. In this article, we will look at the features CP includes in there standard series pistons.
Some of the features includes a double pin oilers, anti-detonation grooves, and light weight wrist pins. CP pistons also have valve reliefs that can clear oversized valves and high lift cams without any modifications to the piston.
Features included in standard series pistons:
-Double Wrist Pin Oilers: Double Pin Oilers are very important option for pistons. Especially in high power and high RPM applications. They allow double the oil flow to the wrist pin to prevent metal to metal contact and wrist pin seizure in the piston bores. These high performance pistons receive oil to the wrist pin bore from oil that is scrapped off the cylinder wall by the oil scrapper ring in the piston. This option allows twice the oil from the cylinder wall to be used for wrist pin lubrication.
-Anti-Detonation Grooves: Anti-Detonation Grooves (A.K.A. Contact Reduction Grooves) do not prevent detonation like the name implies. They just disrupt detonation forces from getting to the top ring of the piston. Why this important is detonation could cause the ring to flutter and lose seal with the cylinder wall. These detonation forces could also break the top ring. These grooves also reduce piston to cylinder wall contact during high temp and high RPM engines. This results in less friction between the cylinder and piston, resulting in less excess heat build up and allows more of the power generated by the fuel charge to be allied to make the vehicle go forward, instead of having to be used to overcome the friction.
-Accumulator Groove: This Grove is a V-shaped groove machined between the top and second compression ring. This grooves accumulates excess combustion gases that got past the top ring. Doing this relieves top ring flutter and premature wear of the second ring.
-Light-Weight Wrist Pins: Light-Weight Pins reduces the reciprocating mass of the piston assembly, which allow for increased RPM operation.
-X-Forgings: The Forgings used by CP on there ATV, MX, and SxS pistons are known as a X-Forging. The X-Forging is designed to minimize friction and weight without sacrificing piston strength. They also have the pin bosses moved inward allowing for a shorter wrist pin to be used. By using different angles and braces, CP is able to balance the weight between high and low stress areas.
There are also other factors that go into deciding which piston to use for your specific application. Factors such as Application, other engine mods, (bore and stroke, etc.), Naturally aspirated or Forced induction (supercharged, turbo, nitrous), 2-ring vs. 3-ring, and many other factors must be considered to find the best piston for your engine.
Please click here to check out some other options offered by CP that can be applied to their off the shelf pistons.