 A key part of the project was the creation of a unique "U engine" out of two existing Simca straight-4 engines.The blocks came from two different Simca applications and rotated in opposite directions but shared the same 1294 cc displacement.One block was from the 1100Ti and was adapted to transverse mounting while the other was from the Simca 1000 Rallye II in which it had been mounted longitudinally.