So I've just got this holset hx32 (hx35 Compressor and core, hx30 turbine) for my sr20det, and planning on welding a 3 inch v band on the turbine housing as suggested. But could I cut the turbine housing back slightly (30mm) as it would give me far more room for a decent downpipe? The turbine wheel is about 9 cm back in the housing so I don't see why 30mm should affect it. Also the paperwork I got with the turbo states the minimum id of the oil drain should be 30mm? That seems massive and the oil drain in the core and the fitting into the sump are both 12 mm. So surely they will be a restriction?
Replace the sump fitting for a 15mm or bigger fitting if you can. And plenty of people cutting turbine housings back on holsets and welding on bigger vbands. No reason I'm aware of why not to, the sooner after tuurbine you can get it bigger the better.
30mm must be a typo, as its like 19mm they always go on about on Holsets. And fuck yeah cut it down, loads do, its better for performance, never mind room. 3in+ from as close to the turbine wheel as possible.
