I know that this has been asked several times, but I could not find the answer which would be satisfactory.

What is the main difference between these two? According to Wikipedia: http://en.wikipedia.org/wiki/Honda_B_engine#B16A

B16A (SiR II) has 174hp / 157Nm
and
B16A2 has 160hp / 151Nm

I know that SiR II has high compression pistons, but there should be something else too? What?

- Header?
- Intake manifold?
- ECU?
- Cams?
.
.
.

I would appreciate your help!

 

It's been covered, the jdm b16 make 170hp from the .2 higher compression, and it's rated on a higher value octane gas from japan