The goal of this project was to increase the power and torque of the C/4 engine while retaining the balanced character and stock appearance of the engine.  In order to accomplish this, we elected to begin with the 5.0 liter engine from the later 412i.  The 412i engine is based on the same Columbo block and made an excellent basis for the C/4 project and to keep with the original character of the C/4, it was decided to keep the 38 DCOE side-draft Weber carburetors, fitted with larger 32 mm venturis.  The engine was equipped with Razzo Rosso forged aluminum pistons with a compression ratio of 10:1.  The stock connecting rods were replaced with steel Carrillo rods.  The stock Ferrari crankshaft was retained. CAROBU Engineering designed and fabricated a new, larger tube, stainless steel header with 1.625” (41.2mm) OD primaries.  Again, in order to preserve the character of the original header, the 6-2 design using flat 3-1 collectors was retained.  A Black Stallion solid state electronic ignition kit with programmable ignition timing was fitted.

Type: 365 C/4-412i Hybrid
Bore: 82mm
Stroke: 78mm
Compression Ratio: 10:1
Heads: good intake porting, manifold matching
Cams: Proprietary “Hot-Street” can grind
Induction: 6 Weber 38 DCOE carbs with 32mm venturis
Exhaust: CAROBU custom-designed headers
Ignition: Black Stallion programmable ignition