Originally Posted by Trey
Good info dave.
The more important question is . . . what does it really matter. a B16A is still a B16. There might be a little more power rated in a JDM motor but first it is likely in PS not HP and 2 you can get that power back in modifications since the likely cause in a higher rating is restrictions the US had on the stock version of the car.
2nd gen B16A's def. made more power then 1st gen ones. 10.2:1 comp on 1st gen JDM B16As and 10.6:1 on 2nd gen B16As, cams were the same IIRC. Intake manifold was different as well. But that's all comparing the two generations of JDM B16As. I'm not familiar enough with USDM B16Ax's to say exactly what's different but IIRC there is a difference in pistons in the later, hydraulic tranny cars. PR3 vs P30 but not 100% sure on that.