Re: kkk turbos , VATN

[mrukir <mrukir@snet.net>]

Gerard wrote:
> 
> > I beleive the variable intake guide vanes allow a smaller turbo to
> > adapt to changing operating conditions.
> 
> Eek! So which is it to be? Is it the impeller (cold side) or the
> turbine (hot side) that carries the variable vanes? Some say the cold,
> some say the hot. I have found only one site dealing with these babies,
> but haven't found the time to go through it yet. Perhaps I should.
> 
> While at it, I have another question to throw out onto the list:
> 
>         What is the best method of control for the variable vanes?
>         I hear a lot of these units have vacumm actuated controls,
>         you can spot the VATN by a diaphragm housing around the cold
>         side, but are there electronically controlled and actuated
>         units out there? Just thinking along the lines of something
>         far fetched such as a CIS to EFI conversion that takes into
>         account the use of a VATN. :) *sheepish silly grin*
> 
> G.
> --
> "a thousand miles from here, there is another person smiling"
> 1990 Turbo (200t, MAC13A ECU, 1.4-1.6 bar, FWD auto)
> name   : gerard van vught
> tel    : +27-21-696 0331 (h) / 082 923 9609 (cell)
> url    : http://www.poboxes.com/gerard/
> e-mail : gerard@poboxes.com  / han.solo@galaxycorp.com
   I don't think you could have varible vanes associated with the hot
side without mucking up your exhaust gas scavenging for the piston
engine.  If you closed down the flow area you'd be choking off your
exhaust.  There are turbine engines that have this feature(the AGT-1500
engine used in the M-1 Tank), but they don't have the added complication
of of having to satisfy the flow requirements of a piston engine while
making the turbine run efficiently.  The materials required to allow
smooth operation at the kind of temperatures encountered in the exhaust
stream, are exotic cobalt alloys which are probably cost prohibitive for
an automotive application.
                               Paul Balko