BBC 325cc Pro-1 Head 121cc R/P 2.25/1.88 Bare

The DART BBC 325cc Pro-1 Head 121cc R/P 2.25/1.88 Bare cylinder head is a precision-engineered aluminum casting designed for Big Block Chevy engine builds. This bare head delivers 325cc intake port volume paired with a compact 121cc combustion chamber, making it ideal for engine builders and performance enthusiasts targeting improved flow characteristics and combustion efficiency without factory restrictions.

The 2.250-inch intake and 1.880-inch exhaust valve sizes represent DART's Pro-1 platform specifications, optimized for mid-range to high-RPM performance applications. The 325cc intake port volume provides the airflow capacity needed for headers and carburetor matching in street and racing engines, while the 121cc chamber volume supports higher compression ratios and efficient fuel burn. As a bare casting, this head arrives unassembled, allowing builders complete control over valve train configuration, rocker arm selection, and port work customization. Weighing 33.94 lbs, the head is dimensioned at 10.4 x 7.75 x 24.3 inches, fitting standard Big Block Chevy mounting patterns and bolt configurations.

Engine builders, machine shops, and performance enthusiasts restoring or upgrading Big Block Chevy engines rely on DART cylinder heads for repeatability and cost-effective performance. This Pro-1 variant suits builders who need substantial intake flow without the premium price of fully ported or race-spec castings. Whether assembling a classic muscle car engine, performance street engine, or competition build, the bare casting format means you source your own valves, springs, pushrods, and rocker arms to match your specific power target and application requirements.

DART's Pro-1 heads occupy the practical middle ground in the Big Block Chevy cylinder head market. They deliver measurable flow improvements over factory castings while remaining more affordable than fully race-ported or CNC-machined heads. The 325cc/121cc configuration works across a broad range of engine displacements and power targets, making it a trusted choice for both first-time builders and experienced engine shops. SKU DRT19200010 ensures correct part identification and fitment.