This is a very simple and helpful mod to keep your non-VTEC B-series block cool, highly recommended for any high output application (200+hp). It involves tapping into the coolant passage from the back of the block.
The oil cooler mounts to the block where the oil filter goes. B18A/Bs and B20B/Zs do not come with an oil cooler however, an OEM oil cooler from 1st gen B16A's, OBDI GSR's, and '97-'01 ITR's can easily be added.

How it works: the Honda oil cooler is like a big hollow donut mounted just between the back of block and the oil filter. The cooler mounts directly to the block, and the filter mounts onto the oil cooler. The hollow passages house the fresh coolant fed from the block's coolant passage. As oil makes it's way to the filter, it passes through the envelope of coolant 1st, thus reducing engine oil temperature. Simple, no? :)

The back of a stock B20B(B20Z and B18A/B are identical):


Overview of the back of a modified B20B(notice the oil cooler in place where the oil filter mounts to the block, also notice the copper coloured fitting where the block was tapped all the way to the coolant passage):



Close-up of above shot:


The tube that runs from the water pump to the thermostat housing must be swapped for a GSR/ITR unit, they are identical in length/width, black=GSR and gold=B20B:


The whole set-up dummied together to give an idea of the finished product:



Important notes:

* OBD2 GSR's and 2nd gen B16A's do not come with this OEM oil cooler. Why not? Your guess is as good as anyone's.
* H22A's come with a similar oil cooler, and since they use the same sized oil filters as the B-series engines, logic would suggest the H22 oil cooler would fit on any B-series. If you have access to one, givie it a try and let us know if it works. :p
* The GSR tube will have an extra hose coming off that's not needed. You can safely plug this up by whatever means.
* The copper fitting for the coolant spout can be purchased at Acura (although an aftermarket piece was used here). Drilling is required to tap the block for coolant.