I just dropped a D15B in my EJ i drove it about 200 mi and now i have a knock... and i lost compression in the 1st 2nd and 3rd cylinders. I'm hoping its just the rings and/or bearings. What i want to know is if the bearings and rings for a USDM d15 will be straight in the JDM block.

 

Not sure exactly what your asking.. Is the engine still on waranty? the 92-95 EX parts are innerchangeable not sure about the Rings havent torn one down yet. Your best bet is the 92-95 Civic EX 1.6 vtec.. So d16z6

 

but from my understaniding the D15b block is smaller so it wouldn't be a direct fit to put D16z6 rings in a D15b they would be oversized..

 

the d15b is a touch smaller then the d16z6 but has higher compession which gives it a little more power but it is a direct bolt in. The d15b is a common motor and you can find the parts you need with some ease.

 

Bad comp in cylindars that are adjacent would signify a busted headgasket.

http://autos.yahoo.com/maintai....html

 

Well a knock isnt usually from bad rings (bad ring are low compression and burning oil), knocking comes from bad rod bearings. I've always thought the d15b/d16z6 blocks were the same, the only difference is the stroke and comp. If thats the case d16z6 rings should work on a d15b.