Heres a bit of info on them:
Mitsubishi uses TD04, TD05, TD06, TD07, TD08...to designates turbo housing.
For example, TD05H-16G 7cm^2 is a turbo with,
- TD05 turbine housing with 'H' style turbine housing/wheel. There are S, SH, H... style of turbine wheel/housing.
- 16G compressor wheel. 16 is the size of the wheel, 1.83 inducer, 2.37 exducer. G is the style of wheel (alternating height of blades). C, B, T style wheel's blades have the same height. Blades are always evenly spaced, but the number of and pitch of the blades can change between models.
- 8cm^2 is referring to exhaust discharge area in the turbine housing. More specifically, it is the cross-sectional area of the smallest intake passage in the turbine housing before the passage spreads around the circumferential volute that leads to the turbine wheel. Very similar to Garrett turbo's A/R. The smaller number means faster spool-up but more back pressure at higher rpm. Bigger number means longer spool up but less back pressure, thus more top end power.
Greddy modifies Mitsu turbos. Bisides, TD04, TD05, TD06, TD07 turbos, Greddy also makes hybrid turbo, T67 is TD07 compressor and TD06 turbine, same turbo as TD06SH-25G. T78 is the compressor of TD08 and turbine of TD07, T88 uses compressor and turbine from TD08.
Gaz.