There is no point in staying with the stock t25 housings etc if you wish to upgrade the turbo.
A cheap upgrade is the T28 from a 200sx or rover 200, but you will need to modify the compressor inlet and outlet to fit as they are flanged not push on. This will flow more air at less drive pressure upto a point. Good for use with a tunit box and the like, spools early and strong, doesnt choke over 3500rpm like the stock t25.
*IF* you can throw in enough fuel, then the GT2056S or GT2256 (WG or VGT flavours) are good. Both of these turbo's are fitted to loads of applications. Must be used with a custom map or aftermarket ecu, otherwise you won't get full benefit.
Standard clutch wont take any more, so thats where I am stopped at right now! lol.
