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Variable Nozzle Turbo Technology
VNT is used on the hot side of the turbo, as someone commented earlier, it
effectively changes the A/R ratio of the turbo. There are 1/2 dozen ways to
accomplish this, all giving the same net effect. The object is to make the
turbo spin faster at a lower engine rpm, then be "less" restrictive to exhaust
flow at high engine rpm. The best of a k24 and k27, all in the same turbo.
There are ways to do the cold side as well, albeit more expensive.
IHI was the first to extensively use the VNT turbo on the Dodge turbo cars in
the late 80's. Very successfully in fact. You will also find VNT technology
on a whole bunch of turbo diesel trucks. Torque figures are impressive,
usually VNT lowers torque rpm by 10-20% and increases that figure by 25% or
more. All good things.
KKK needs to respond to the changes in the turbo market, IMO. Right now,
ceramics and lightweight inexpensive turbos are hitting the market. The only
thing, IMO, saving their hides with audi turbos, is the exhaust flange. I
hear that is about to change too. So, they should start coming out with some
new stuff, share some more MAPS, and let the market forces create the demand.
You need to improve and innovate to create that demand. Or, as the ad says,
get out of the way.
BTW, Ceramic ball bearing turbos are used for longer life, better heat cycles,
more thrust load and less rolling resistance. The ceramic wheels are next.
The advantages there will be less lag, more power and lower cost. It's all
coming, here's to hoping the market drags KKK kicking and screaming into
My .02, hardly objective :)