So I've been keeping watch over the past two years (as many others have..and for longer) for hybrid turbos which retain the sequential operating system and offer significant hp gains.
Well Stu Hagen, King of the Sequential twins (not necessarily "stock" sequential twins in this case), has come up with this exact option. Below please find a link to the initial discussion from the dyno section. #49 on pg. 2 is where it gets interesting.
One beta tester already has these on. I'll let him come on board with the specifics but basically he is finishing up the plumbing and then he'll be putting them on the dyno. and doing a "how to". I will be doing the same as soon as I get my pair.
He also has a manifold which will allow these turbos to really breathe. Inner diameter of the turbo inlet is the same as the ID of the piping. 600+ on race gas should be possible with this setup.
Hopefully the guys on the "other" forum will chime in here and help this get rolling also as I've cross-linked the threads . Big thanks to Stu and all the others involved in this project. They add so much to the Supra community.