the one you have now describe the rb 25 turbo also it should not have a hole for the line going to the waste gate actuator on the compressor housing. they are rated @ 280-300 hp each there are no comprssor map for them the are a hitachi turbo which is a copy of a garret t28 with a t3 flange
this is what they look like note the numbers on the comprssor housing
meggala