Paul,

Chris Wood was nice enough to introduce me to this firm that sells many
different turbo-charger parts. Between looking at about 30 pictures and
comparing shipping weights and knowing flange sizes I can finally
guesstimate the dimensions of these beasts.

http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GRT-TBO-005&Category_Code=GRT

One question.   Are there any advantages to a split mouth like Mazda uses
verses open mouth inlet to the turbine?   I am wondering if Mazda's
choice  has anything to do isolating  the strong exhaust pulses.


Doug in Japan

Mazda tried it for awhile and gave up. Something to do with recovering
the pulse energy. I am not sure why they gave up.

Read this. They talk about the twin scroll here.
http://www.rotaryeng.net/2nd-gen-turbo.pdf

Paul Lamar