This guide will prove useful when purchasing a B16a engine. There are a number differences between the generations, which could effect engine re-build, hybriding process and of course price.

Fact Sheet

Valve Specs (Note that Honda measures valve timing /lift at 1mm of lift)

Comparing only the JDM motors, the first generation B16A has a lower compression ratio (10.2:1 versus 10.4:1) and makes 160ps instead of 170ps of output power. In addition there was a revision of the cam profile and oiling improvements in the second (and later) generation B16A engines.

Open the oil cap, you should be able to see the oil spray bars. The first generation has cast aluminium oil spray bars while the later generation ones are made of extruded aluminium. The difference in ECUs mean fuel injectors/harness, distributor and plugs are not interchangeable unless they are converted.

1st gen. B16a heads supposedly have less 'core shift' compared to 2nd gens. meaning 1st gen. heads have better quality castings. Core shift occurs when the casting (2 molds pressed together with molten aluminum poured in) shifts from it's original position, causing slight differences between each side. This can cause problems when you port the head because some surfaces might have less material than others.

External Differences

	1st Generation	2nd Generation
Valve cover	1st gen. Has a smaller 'VTEC' inscribed and has 'Honda Motor Co.' inscribed whereas 2nd gen. has 'Honda'. (Note: Valve covers are easy enough to change around so beware).
Intake manifold	PGM-FI label and vacuum dash-pot	Absence of PGM-FI label and vacuum dash-pot
Connector plugs on engine harnesses	Milky white in colour	Grey in colour
Throttle body	Extra tube for remote mounted MAP sensor. 58mm ID	MAP sensor integrated with TB. 60mm ID
Fuel rail	Cylindrical shaped	Flat rectangular shaped
02 sensors	2 single-wire sensors	1 4-wire sensor

Manual and Automatic Tranny Differences

Automatic equipped B16as are lower spec'd. They miss out on dual valve-springs on the intake side and their cam profiles are not as aggressive as manual equipped B16as. Their ECUs have lower rev limiters as well.