just a question are the 99 and up b20z oil pumps the same as the type r or do i still need to get the type r oil pump for my b20 vtec i heard they are the same would like to know if they are

 

They are all the same. the B20 will work fine

 

there was difference in rotation ratio, but can't remember was for the oil or water pump.
​​​​B18c b16 pumps are equal for sure.
b20z pump has to rotate faster due to lower OEM engine rpm. Providing same amount of pressure.
It has less tooth on the pulley.
​​​​​​as far to remember was a couple of tooth less.
​​​​​​

 

All B series oil pumps superceded to the P72 many many years ago. The oil pump does not have a pulley, it is driven directly by the crank.

You are confusing the oil pump with the water pump which does have a smaller pulley for the non-vtec models. You can use the vtec specific water pump on a non vtec engine just fine (you also need to use a B18C timing belt if you do this), but you really shouldn't go the other way (use a non vtec water pump on a vtec engine).

 

Yeah, if we are talking about genuine spareparts, maybe +10 years there's has only two option for B-series engines, "PR4" and "P72". They both have a same internals, only differ is pump housing because there's CKF-sensor mounting point in "P72". Rotors (80mm od), pressure control valve and spring, all the same.

In 90's OE-pumps there's little varies, some early one's have a 84mm rotors so then housing differs, but nothing drastically.


On top (two pumps) are 80mm rotor versions. One from 96-00 B16A2 and genuine spare, "PR4". Below 84mm version from 92-95 B16A. I have also OE-pump from 98-00 B18C6 but not in pics, it is equal to top ones.





So, the differences. Pump gears of course, and 84mm have a little wider inlet channel and outlet's entrance is smoother. But like I said, nothing drastically.

80mm left and 84mm right.




Inlet from 84mm version.




Outlets entrance from 84mm version.




Also, newer pumps (P72, PR4) got stiffer pressure valve spring (69mm) when older one's have a 68mm. Spring wire same 1.9mm.
Btw, this new springs is exactly same as K-series, even same part number (15232-PG6-000).




Valve piston desing is same in all pumps.





But there's good details whereof you can identify which one is which, without disassembling whole pump.

80mm pumps has that "square" front of the pump housing (front/ headers side of engine) and 84mm's do not.




Another detail from 80mm's housing.




Bonus, Toda HD oil pump gear vs. OEM. Same desing, different material. Toda weight 226g and OE 200g, inner and outer rotors are both ~13g heavier.