Not too long ago, Bryan Moreland, Engineering Manager at CP-Carrillo sat down for a virtual chat with professional engine builder and race shop business owner Joey Grose, of Grose Racing Engines to discuss piston development and assessment. The discussion was orchestrated and overseen by by Brad Gillie of SiriusXM Ch. 90, Late Shift on the EPARTRADE YouTube channel.

CP-Carrillo has long been known for its development of all manner of piston solutions and has been making a stir in recent years with its advanced engine analyzing and production methods. From supercross and boat racing to tractor pulls, road racing, and everything in between, CP-Carrillo has taken the initiative to develop and construct everything in-house. Everything from two-stroke to four-stroke, this brand has you covered with its extensive line of pistons, rods, and hardware.

Grose Racing Engines has been a CP-Carrillo distributor and supporter since the company’s early days and utilizes the firm’s components in the engines that it builds for customers, as well as those that it races in the shop’s Pro Stock car.

Shooting the breeze at the racetrack, brainstorming build solutions, and conducting engine tear-downs together have been a compelling part of the relationship between the two companies, and now we have an inside look at how that is aiding (and changing) piston development for the rest of us.

Modern CAD models really have made modern custom piston production an incredibly efficient process.

Break It and Then Build It Better

Although race-specific applications make each customer’s needs unique, Grose’s drag racing platform has consistently provided an easy and reliable solution for real-world engine analysis. Routine teardowns not only allow mandatory engine inspection on the spot, and parts analysis post-race, but they also expose any weak links or issues.

Naturally, anything catastrophic requires a full autopsy back at “the morgue” at CP-Carrillo headquarters, but that is to be expected. This protocol allows the firm’s engineers to analyze what happened and why so that any design flaws and/or inferior materials can be improved going forward.

CP-Carrillo prefers to have parts shipped to its company headquarters any time something catastrophic happens, regardless as to whether it is on track, during a dyno session, or while cutting donuts in the supermarket parking lot.

Offering the driver and/or engine builder some insight into what went wrong is also invaluable, especially when nothing was fundamentally wrong with the piston and rod combo churning inside. Remember, piston failure is often due to driver error or improper installation, and not due to some design flaw or material failure within the component itself.

So exposing what went wrong is very important in this regard. Catching these things as they happen is also a huge help for companies like CP-Carrillo, as it allows them a first-person account of what happened and early access to the injured engine itself.

Send It!

In Grose’s case, he prefers to ship things like entire cylinder heads and whatnot back to CP-Carrillo for analysis when things go sideways. This allows the company to scan everything via the use of a contact-based Coordinate Measuring Machine (CMM) system. Such an approach is also taken for a new engine build, when a piston dome profile must be determined, thus allowing a completely bespoke product for a specific racing strategy or chassis application.

Since Grose constructs his own cylinder heads from scratch, CP-Carrillo is allowed to do things like mirror the bottom side of each valve onto the piston itself for maximized efficiency and volume. As expected, the primary goal is to construct a product that can create more power and last longer.

As Grose explains in the online chat, back in the day they had to cut their own ring lands and form pistons to the specs they needed, which would oftentimes take weeks to accomplish. But nowadays companies like CP-Carrillo can take raw CAD files and construct a product around the digital rendering itself. This way there is no need to wait for a physical “hard copy” of a product to arrive, and all you need is an email with an attached folder filled with CAD renderings.

In Grose’s case, he prefers to test new CP-Carrillo products both via dyno testing and in his boats prior to approving the engine configuration and placing it in a race car. This allows additional levels of R&D testing and quality control to take place in a real-world environment. 

CP-Carrillo Stares Down the Track

As of late, CP-Carrillo has gotten into OE piston manufacturing, which in turn has helped bolster the brand’s aftermarket clout. This has spilled over into the racing side of operations, and according to Moreland has been “very beneficial” in how the company develops its products. Furthermore, CP-Carrillo has begun using air gauging for volume measurements and has slowly been integrating robotic machining into its operations to eliminate the risk of human error.

Even then, Moreland encourages clients to plan out what their needs might be ahead of the off-season and consider turnaround times. While emailing a CAD file does eliminate the shipping times associated with mailing engine blocks to CP-Carrillo, things like reverse engineering and under-head milling always take more time, regardless of what fancy tech is tackling the project behind the scenes. How long you might ask? Anywhere between 4-8 weeks depending on the complexity of the project at hand.

To help further streamline any bottlenecks in turnaround times, and offer a more affordable option to automotive enthusiasts, CP-Carrillo launched its Bullet Series of pistons and rods.

When asked about what CP-Carrillo developments were in store for 2024, Moreland explained that the plan is to include shaping wrist pin bore housings more regularly. While long considered a mandatory motorcycle and OE necessity, this additional step has recently been deemed necessary for more and more race applications. Apparently, this allows the wrist pin to adapt to the bore better when under load to reduce strain and increase longevity.

There has also been some discussion about the advancement of manufacturing some of the first “printed pistons” in CP-Carrillo history, and combining this with the new piston material advancements the metallurgy masterminds have been dabbling in down at the company’s laboratories. One thing is for sure, the future of performance pistons is brighter than it’s ever been.