My RX6D turbo is dying and fuck buying a RX6R to replace it with ($2400 turbo) not to mention they don't even make them anymore. So, I'm wanting to convert my manifold from the IHI flange (elongated T25 looking flange) to a T3 flange. My manifold is a old cast iron apexi manifold, but as you can see from the dyno plot below, its already proved it can support nearly 500hp.



I'm wanting to swap to a T3 flanged turbo that will make similar, or more power. So far I'm thinking either a BW S259 w/.70 AR hotside or a GT3582R w/.63 AR hotside.

My other major question is what kind of welding will it take to do this, and how much will it cost (ballpark). I've got a turbo elbow for the setup on the car now, which i imagine could just be cut, extended and reflanged for the new turbo's outlet pattern.


Cliff notes for Martin.

1. Old IHI turbo dying
2. New turbo is going to be t3
3. Must convert downpipe/turbo elbow & manifold to work with new turbo