96 mm cylinder question, Difference between 1.7- 2.0? Options

[Jgilliam914]

I was digging through a storage tote and found a set of NPR 96mm pistons and cylinders.
Is there a difference between one that fits a 1.7 vs a 2.0?

[914sgofast2]

The 1.7 liter and 1.8 liter rods are the same length. The 2.0 liter engine's rods are a different length because the 2.0 engines have a different crankshaft stroke.

The two types of 96 mm diameter pistons available for these engines are also different. The pistons used in the 2.0 engine and the 96mm pistons used with the 1.7 liter and 1.8 liter rods have different piston pin heights within the pistons.

When aftermarket 96mm "special big bore" pistons are used with the 1.7 or 1.8 engine's rods and crankshafts (along with 96mm cylinder barrels), it will only yield a 1912cc displacement, not a true 2 liter displacement.

If you want to turn your 1.7 or 1.8 engine into a true 2 liter engine, your need to use a 2.0 liter crank and 2.0 liter rods. These are "bolt in" updates to the engine case without modifying the case.
Cylinder heads are a slightly different matter. The 1.7 heads will need to be fly-cut to accommodate the larger outer diameter of the 96mm cylinder barrels. The 1.8 heads do not need to be fly-cut, and have a head/combustion chamber diameter which will handle the larger diameter 96mm cylinder barrels.