Hello All,

I figured this was the correct place to ask this question but I am new so please let me know if I am in the wrong.

I recently put a CXRacing turbo kit on my 1990 Manual Miata. It comes with what they call a T28 turbo (Seems to be wet float bearings, not ball bearing) and I need to restrict my oil in line to 0.060in as recommended (although I could be wrong).

My question is does anyone know what kind of thread would be in the turbo housing? I have not had any luck figuring it out. I got my hands on a restrictor from a GT28 (I think) that is drilled to the correct orifice however the threads on the turbo side of the fitting seem too fine compared to the fitting that came with the kit and after test fitting, it only goes in maybe 1 turn.

Also to note, I tried running it without a restrictor and it smokes a little when my oil pressure goes up so I feel confident it is not internally restricted.

Any insight is much appreciated.

-Ronan

 

 

Haha, thanks for the insight. Cant say I didn't see it coming...

 

go to the kinugawa website. they will have what you need atm. or go to the garret site and learn about what you need in regards to the orifice size.

 

Thanks for the info ryansmoneypit, I have taken a look and they have a lot of fittings. Thanks for the help!

 

This is what my Garret t28 has with it.

​​​​​​​https://frsport.com/DIF-10016-Turbo-...-_p_16397.html

 

CX Racing lists the T28 as using an M12X1.0 oil fitting thread. Your’s is a journal bearing so probably use a .060” restrictor.

Amazon:

 

You can see what size bolt fits in it, by bringing the turbo to the hardware store. Or buy a few bolts- mark them, and bring them home with you until you know the size for sure.

 

Some turbos come with 7/16-24 thread instead of M12*1.5 (WHY ARE WE STILL DEALING WITH INCHES).
Try ordering one of those instead of the M12.