Whats the difference (or is there any) between the b18c1 block from an obd1, 2a, and 2b car?

 

I think the block is the same, because OBD represents On Board Diagnostics, and controls more of the emissions. Then again, I could be wrong, cuz I know the B18A in a 91 integra has 10 less hp than a 93. Bump for more info!

 

Yeah I wasn't sure if there were extra sensors or anything on the actual block for the obd2s vs. the obd1s, etc.

 

OBD-2 engines had a CKF sensor mounted on the oil pump, and a revised lower timing belt cover was used.

Lack of oil cooler on OBD-2 engines, which facilitated a change in the main water pipe. I'm not sure what happened to the coolant return nipple in the block tho now that I think about it.

Simplified coolant routing that used a revised thermostat housing that is sans an 8mm nipple.

The actual block casting and internals are unchanged (except for maybe the oil cooler coolant return nipple). It's the stuff surrounding the bare block that changed.

 

so, for example, a gsr bare block from an obd1 would be the same as a gsr bare block from obd2 then?

 

Yup, with maybe the exception of the coolant nipple for the oil cooler.

 

cool, thank you