TDO4 13G.....anyone tried this?

[jimbote]

Scored an almost brand new TDO4 mitsu turbo from a cat skid steer engine (mitsubishi power).....wondering how this might work for my TDI M.....the kicker is that it has no wastegate or blow off.....so does this thing just run max boost all the time at throttle? I guess I can add an external wastegate to the adapter flange..... sweet looking turbo ......any ideas?

[RabbitGTDguy]

sometimes turbo such as that can be pretty inefficient...however, it'd would really depend on what the A/R markings are on it, etc
Do you have these? It'd be interesting to know what the cold side and hot side A/R's are to give you a better idea of "how" it would do.

Also, with no wastegate (and turbos don't have "blow off valves" anyways...they belong in the intake track itself...usually attached to an intercooler tube downstream of the throttle on a gasser...) it would run "wide open" and probably more than likely had the control of the motor it was on itself, of low RPM operation that kept from the need of having a wastegate. It could have also been external as well.

The size of the unit would be interesting to see...

Joe

[jimbote]

Hmmm....I'll get these numbers today when I'm at Pop's shop....I took the turbo off the engine so I know it does not have any boost control (or intercooler).....the intake and exhaust wheels look rather large so it may not be a good one for my dreams.....but I'll get back with the numbers....

[QuickTD]

the kicker is that it has no wastegate or blow off.....so does this thing just run max boost all the time at throttle?

 In most "free running" (non wastegate) turbo applications the boost is controlled by a combination of turbine housing A/R and limited fueling. The larger turbine housing required to keep the boost in check will produce little boost at low rpm, but since the skid steer normally runs at a relatively constant governed high speed, this setup works well.

 On an automobile the situation is different, the engine is expected to pull well at all speeds so a wastegate turbo with a somewhat smaller than optimum turbine housing is usually used. This allows the engine to make good boost at low rpm and the wastegate allows some exhaust to bypass the turbine at high rpm to control boost.

 I would guess that your skid steer turbo would produce pretty dissapointing low end power but may do well at higher speeds, depends on the A/R and wheel sizes. If the turbine housing is too small to control boost an external wastegate could be added.

 The displacement, hp and maximum rpm of the mitsubishi engine will give probably give you some clues as to the capabilities of the turbo.