Identifying the Honda B16A Engine

Which is Which
Beginner’s guide to telling apart B16A motors

by Adrian Teo
10/06/1999

 

With all the misinformation that has been passed around by word-of-mouth and the internet, quite a few individuals have made the mistake of buying the wrong B16A engine (often not realizing it).  What this page tries to achieve is to clarify some of the doubts when it comes to which B16A is which and hopefully stop retailers passing off first generation B16A’s as later generation (92 and up) B16A’s. 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.   What to look for Japanese market (JDM)  B16A motors are  labelled with a “B16A” stamp. There is NO suffix (e,g, B16A2 or B16A3) like the US, Asian or European counterparts. Hence it isnt easy to tell just by looking at the block stamp. Below is anpicture of a B16A from a 92 JDM EG6 (SIR-II). From the picture, you’ll notice the following. Absence of a PGM-F1 label on the intake manifold. The Intake manifold has no bulge on the back side (side facing the firewall). Connector plugs on the engine harnesses are grey instead of milky white. Absence of vacuum dashpots on the intake manifold and throttle body. MAP sensor is an integral part of the throttle body, not an external one with a tube.
Externally (not seen in this picture) you will also see: Single 4-wire O2 sensor instead of 2 single wire O2 sensors Look at the images below. Both serial numbers start with ’5′ bit the left one is a later generation B16A and the right one is a first generation B16A (click on the images to magnify them).
2nd generation B16A Grey connectors One 4-wire O2 sensor Hydraulc transmission	First generation B16A Milky white connectors Twin single wire O2 sensors Cable transmission
Things to ignore: Valve covers. It’s too easy to change valve covers. This next picture is from a 94 JDM CRX SiR (EG2) You will notice the same features that tell it apart from a first generation B16A. The differences do not end there. If you 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.   Price issues The going price of a first generation B16A varies at around $400-$800. Sometimes this price includes a cable clutch  transmission(Y1/S1/J1). The later generation B16A price is obviously higher, raging from $1500 to $3000. For $3000, expect a hydraulic clutch transmission (YS21) to be included. It has come to our attention that some retailers have tried to pass off the first generation B16A as a late model B16A and hence selling them for much more than they are worth. Please be very aware when buying these motors.

Information Source: www.hybridgarage.com