Here is an early outside plug 250 engine from a PF Cabriolet. The valve sizes were smaller then the later heads, so the power wasn’t great. Still the engine is all stock, so the numbers are representative of the era. This engine also has the early 6 into 1 exhaust manifolds, which were less efficient then the later ‘split’ type headers. All this adds up to a relatively docile engine, which is in character for a PF Cabriolet. Unbelievably, the factory rating was 240/260 HP at 7000 rpm.
Type: 250 GT
Compression Ratio: 8.6:1
Induction: 3 Weber 38 DCN carbs
Exhaust: stock 6 into 1, dyno mufflers