Dougs951S

I'm finally getting around to installing my HX35, now is a good time since I'll be pulling my crossover to have a crack tig welded. I will be using the holset center section and compressor and mating it to a turbonetics replica KKK hotside. These replica hotsides are designed to accept garrett center sections, so I will have to very slightly reduce the OD of the holset center with a dremel where it slides into the hotside. None of this is a big deal. The thing I have a question about is how to make the much larger holset turbine fit into the space provided for a Garrett T31 turbine. I plan to just cut out material with a carbide end mill, but do I need to ensure a proper turbine-to-housing clearance, or should I just roughly cut it to fit? My logic tells me the clearance isnt vital, since people very commonly have turbos with a given turbine size, and then decide to go to a larger hotside without changing the turbine. This would increase the clearance I think, and they still perform fine so to me that tells me that what I am doing is similar and to not get too hung up on how much material I remove so long as it fits. Someone please tell me if I'm wrong before I ruin a perfectly good and somewhat hard to find replica housing.

Edit: Seems Holset specifies .019" wall to turbine clearance, but more is probably better since the exhaust will be hotter than a diesel and the wheels will expand more. I'll try shooting for .030.