M838T & M840T
Engine Program

There is no better McLaren engine build, period.

A McLaren engine built by Cannonball Garage is fundamentally different. Not because of marketing claims, but because of the components inside it.

Every CSO engine incorporates exclusive, purpose-built parts that cannot be sourced anywhere else. These components were co-designed by our head of special operations in collaboration with top-tier manufacturers, engineered specifically to solve known limitations in the McLaren platform.

When an engine is built elsewhere, these advantages simply do not exist.

CSO Exclusive Engine Components

CSO MLX Head Gaskets

Our CSO MLX head gaskets feature proprietary cooling ports and custom thickness options that allow us to compensate for material removed during head decking. This preserves proper geometry, compression ratio, and piston-to-valve clearance.

The common alternative used elsewhere is a 765 or Senna gasket for added thickness. That solution requires excessive material removal to function and provides no additional thickness benefit for 765 or Senna engines. The result is compromised compression ratios and reduced valve clearance with no real upside.

CSO Connecting Rods

CSO connecting rods are manufactured from a proprietary material that dramatically increases strength while maintaining factory weight.

Maintaining OE rod weight is critical on a flat-plane crankshaft for proper balance and longevity. Each CSO rod is capable of handling approximately 250 horsepower per cylinder, supporting engine outputs up to 2,000 horsepower without compromise.

CSO Main Bearings

CSO main bearings are the only McLaren bearings available in multiple sizes, just like OE. This allows us to precisely set oil clearances for any application, whether using factory main bolts or high-yield-strength fasteners.

Other builders are limited to single-size aftermarket bearings, removing the ability to properly tailor clearances and increasing risk under high load.

CSO-Spec Total Seal Piston Rings

Developed exclusively with Total Seal, CSO-spec piston rings are engineered to complement the factory pistons and cylinder sleeves.

The result is superior ring-to-cylinder seal, increased performance, and reduced blow-by. In contrast, most builds rely on reused OE rings, leaving performance and reliability on the table.

CSO-Spec Forged Pistons

For clients seeking the ultimate solution, CSO forged pistons exceed OE strength and design standards while remaining weight-matched for proper flat-plane crank balance.

Strength without balance is not an upgrade. These pistons deliver both.

CSO-Spec Cylinder Sleeves

At high horsepower levels, factory cylinder sleeves become a limiting factor. CSO sleeves are engineered to handle extreme output and are significantly stronger than OE and far beyond the few manufacturers simply duplicating factory designs.

CSO Head and Main Studs / Bolts

CSO fasteners are specifically designed to work within the structural limitations of the OE block and ladder frame.

Using improperly engineered hardware risks thread failure, distorted bearing housings, and irreversible block damage. We have documented the results of those failures firsthand.

Why the World’s Top McLaren Tuner Recommends Cannonball

There is a reason the most respected tuner in the McLaren world sends clients to Cannonball Garage.

We do not assemble engines using off-the-shelf components designed by third parties for mass-market profitability. We design our components directly with manufacturers to be the best possible solution, without compromise and without price dictating engineering decisions.

Our Promise

Our commitment is simple.

To be the best, not the cheapest.

The choice is yours.