(OZBooster @ Sep. 18 2006,16:12) Which t25/t3/t4 any of these in the right trims and a/r's will do well for many applications and many of these will be ex diesel engine turbo's with much larger ex and smaller inlet than you would want.
You will want an ex with an a/r of .48 or 63 and visible face of the ex wheel ~47-50mm
the compressor can be a little more open but the smallest you would want is a 42 ar with a 47mm comp wheel face, and probably not larger than 54mm wheel face and ar60.
This is only a guide to be absolutely sure the id numbers or accurate measurements of the largest /smallest diameters of the wheels and a/rs of the housings would be needed