Another orphan engine that sat in a marque specialist shop for over a year before the owner pulled the project, which was still in boxes. The mandate for us was to make 130-plus horsepower in street driving tune with good torque. The Big Valve specification was ordered in Stage II trim. We had to have custom pistons made because the bore was too large for the pistons that were originally provided. This allowed a higher compression ratio (10.5:1) over stock, which is 9.5:1. A fair amount of work was done to the head to improve the intake flow about 13%. For added security, we replaced the stock rod bolts with stronger ARP bolts, but otherwise the lower end was stock. An aluminum flywheel helped reduce the rotating mass and free up a little power. Overall we had a good- if not unexpected- result considering the dyno test was done with the stock air cleaner assembly and exhaust mufflers.
Click thumbnails for larger images.
Power: 131-hp @6,200-rpm, 121 lb/ft of torque @4,700-rpm
Type: Lotus Twin Cam, DOHC, 2V, 4-cylinder
Bore: 83.7-mm Razzo Rosso forged racing pistons
Stroke: 72.75-mm
Compression Ratio: 10,5:1
Cylinder Heads: Big intake valves, street porting
Camshafts: DB114, 243/243 duration (@.050") and 10.4/10.4-mm lift (in/exh)
Induction: Weber 40 DCOE carbs, stock air filter assembly
Exhaust: Tubular headers with mufflers
Ignition: Lucas distributor
