We have learned from an early owner that SB2237 was originally delivered with a pre-crossflow engine with one Weber 40DCOE 2. During its life, the car has been equipped with a number of different engines, including Holbay and Cosworth racing trims.
Today, it is again equipped as when it was delivered, with a 1500 cc pre-crossflow engine and the single Weber mounted on the original Lotus alloy inlet manifold. The manifold was kindly provided by a previous owner.
The performance of the basic engine is moderate, 66 HP at 4600 rev/min. Therefore, the ports of our engine have been enlarged and the combustion chamber has been flowed moderately. Also, humps and edges in the inlet manifold have been smoothed out and the exhaust is 4-2-1. Most importantly, the engine is equipped with a GT cam.
With the 0.06″ overbore our data show a power output of some 80 HP at 5200 rpm. Not a high revving engine but an engine with good midrange torque.
With this setup up the car is lively and has no hesitation during acceleration.