Why a three piece pushrod?


Before we explain why we manufacture only modular pushrods, we must first stop and describe the function of a pushrod. In simple terms, pushrods transfers energy from the lifter to the rockerarm. If a pushrod is not correctly matched to the application, incorrect valve lift and valve timing can cause engine failure. With a properly matched pushrod you will achieve maximum horsepower and ultimate valve train wear.
To achieve the proper pushrod for an engine, you must decide the pushrod length, diameter, wall thickness, materials, heat treating and end configurations to match the specific engine components and application. This may seem like a fairly easy process but to accomplish this there are several things that must be considered. This is why we only manufacture custom modular pushrods.

  • 1. Each end in a pushrod must be compatible with its mating components. This requires the use of material that can function as a bearing and at the same time be as impact resistant as possible. As an additional benefit, this also allows for an unlimited amount of tip designs.
  • 2. With a modular pushrod it allows the flexibility to choose “unique” tapers for clearance issues. Also changing the wall thickness, diameter and tapering the tube will change the natural frequency.
  • 3. The column of the pushrod must be made out of a different material and heat treated differently than the tips. It must provide the strength to withstand the combined abuse of high engine speeds and cylinder pressure. By using a dissimilar material from the pushrod end we are able to utilize any heat treat we desire. In most applications we use a material that is commonly available 4130/4135 tubing. In our series 2 & 4 we use a MeloniteTM process for durability and wear resistance for guide plate use. In our series 5 we use a proprietary heat treating process to increase the material value to a Rockwell of approximately 46 “C”. This is critical to the function of a pushrod column and 4130/4135 is very tough, forgiving and durable when used at approximately 46 Rockwell “C”. We also offer a proprietary heat treated solid bar S-7 tool steel pushrod which is the same material used to produce quality chisels and hammers. It is very impact resistant and is the perfect material for extreme applications.

In our estimation the only reason to ever produce a one piece pushrod would be because of the reduced cost to manufacture. We are here to produce the highest quality pushrods available and for the reasons listed here we DO NOT manufacture one piece pushrods.

three piece pushrod
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