It's identical in effect to any variable geometry turbo... It just happens not to use adjustable angle vanes, rather a sliding vane ring.
As you can probably see, as the vanes go further in, the orifice the gas can fit through is smaller, therefore the gas has a higher velocity when hitting the turbine wheel.
Part 1: Don't think of it "like a HX55" without and with you get "fast spool". Since with the vane ring slid back all the way, it'll have an larger effective A/R than the largest turbine HX55. But yes, when the vane ring is slid all the way in and the orifice closes up, you'll have greater EMP and a smaller effective A/R.
Part 2: Best way is to take the current actuator, strip it down and put the spring on the other side of the diaphragm. If not - I've not seen many that are actuated by pressure that pull the rod in, so probably a mechanism to reverse the action - sure there's enough room to fab something up. Seen the same done on a GT2256V down the back of an XUD before now.
The way Stav did it is hold it with a spring on the vane ring lever so it's purely the exhaust pressure causing high pressure on the vane ring and forcing it backwards under higher EMP, then regulate the overall pressure with an external wastegate. Not how it should be done, but yeah, it'll work.
![[Image: 10626750_926241040725271_3483129862565265846_n.jpg]](http://i1115.photobucket.com/albums/k541/Monkeymagic2/10626750_926241040725271_3483129862565265846_n.jpg)
But yeah, tbh, in the case of that car, it's not requiring much boost but has mega exhaust gas energy... Diesels need nearly the opposite of that - they have relatively poor exhaust gas energy but need lots of boost.
As you can probably see, as the vanes go further in, the orifice the gas can fit through is smaller, therefore the gas has a higher velocity when hitting the turbine wheel.
Part 1: Don't think of it "like a HX55" without and with you get "fast spool". Since with the vane ring slid back all the way, it'll have an larger effective A/R than the largest turbine HX55. But yes, when the vane ring is slid all the way in and the orifice closes up, you'll have greater EMP and a smaller effective A/R.
Part 2: Best way is to take the current actuator, strip it down and put the spring on the other side of the diaphragm. If not - I've not seen many that are actuated by pressure that pull the rod in, so probably a mechanism to reverse the action - sure there's enough room to fab something up. Seen the same done on a GT2256V down the back of an XUD before now.
The way Stav did it is hold it with a spring on the vane ring lever so it's purely the exhaust pressure causing high pressure on the vane ring and forcing it backwards under higher EMP, then regulate the overall pressure with an external wastegate. Not how it should be done, but yeah, it'll work.
But yeah, tbh, in the case of that car, it's not requiring much boost but has mega exhaust gas energy... Diesels need nearly the opposite of that - they have relatively poor exhaust gas energy but need lots of boost.
