TO4 turbine housing swap possible? *Pics Inside*
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I have this turbo, my dad gave it to me. The compressor would be fine but the damn turbine housing is HUGEMONGO. Can you say an A/R of ~1.3.
Is there a way to swap turbine housings. I have no idea what vehicle this turbo came off of, but I'm going to assume it came off a big diesel.
The wheels are perfect and the shaft has minimal play, not out of spec by any means. This turbo is alot like what lazzer had and used for his compressor swap. Does anyone have any idea what kind of housing I might be able to swap onto this badboy? I could just sell it to recoupe some cost of a different turbo. Or I could find a smaller T3 and swap the larger compressor like lazzer. Open to all opinions and options outside of bolting it onto the miata to see when it would spool. I'm guessing 5k rpm. It would be great to find out that I could just swap on a smaller A/R turbine housing.





Is there a way to swap turbine housings. I have no idea what vehicle this turbo came off of, but I'm going to assume it came off a big diesel.
The wheels are perfect and the shaft has minimal play, not out of spec by any means. This turbo is alot like what lazzer had and used for his compressor swap. Does anyone have any idea what kind of housing I might be able to swap onto this badboy? I could just sell it to recoupe some cost of a different turbo. Or I could find a smaller T3 and swap the larger compressor like lazzer. Open to all opinions and options outside of bolting it onto the miata to see when it would spool. I'm guessing 5k rpm. It would be great to find out that I could just swap on a smaller A/R turbine housing.





Last edited by cjernigan; Aug 20, 2007 at 08:50 PM.
I'd pick up a t3 in a 63 or 48 AR housing then use the coldside from that turbo to build your hybrid.
Or.. get a bigger t3 turbine housing and have a machine shop make the wheel fit correctly.
Or.. get a bigger t3 turbine housing and have a machine shop make the wheel fit correctly.
pretty much the same here...not only will you have to find a t3 exhaust assembly but you'll have to get it balanced too...but heck i would just sell that turbo and buy a new one!!!...just to save the trouble and time..
That's just like the compressor I just swapped out on my Saab T3 with the .48 turbine. Works great so far. Mine looked like this after I cleaned it up. I didn't get pics of the t3/t4 I made with it yet.

Here's the t3/t4

Here's the t3/t4
Last edited by lazzer408; Aug 27, 2007 at 01:18 AM.
The turbine wheel needs X cfm of air flow passing over the blades to work efficiently. Amount 'A' comes from one port, Amount 'B' come from the other port and together total X. It's a divided housing to keep turbulence down inside the turbine housing. It's still too large a turbine for 1.8L of exhaust gas to spool.
yes theoretically by limiting the inport to 1 you will increase the exhaust velocity but i dunno if you are gonna run into choke flow issues doing that. I sure wouldn't try. Chad don't you have a s60 laying around somewhere?
Yes you would but the wheel still needs a much larger volume then the Miata can flow even if the velocity is increased. The T4 radius is to large to get any real velocity. If I took the wheel from that turbine, and machined a T3 turbine housing to fit, it might spool it eventually. =) hmm I might look into doing that if there's enough metal in the T3 to allow it.






It's an interesting idea, if nothing else.