while the b engine carried features like bore centers and bearings over from the original triumph design, it was a substantial redesign. like the triumph slant-four it was developed from, the b engine's block is made of cast iron, and the cylinders are canted over at 45° from vertical. the stroke of the earlier engine was retained, but the bore was increased to . other changes from the triumph slant-four included a new cylinder head with bigger valves, enlarged ports, a new combustion chamber shape, and a camshaft assembly redesigned for better lubrication. intake systems for the saab 99 had included fuel injected versions from as early as the 1970 model year, and this continued with the b engine, along with both single- and dual-carburettor setups.