The engine is the later 4.2 with 2 Zenith-Stromberg carbs. This is also VERY easily converted to the Series 1 triple SU’s – though from a performance standpoint, you can do just as well with these carbs when properly tuned. One of the fastest cars we ever had come through the shop when I was a kid was a bone stock ’68 OTS with the same 2-carb setup.