@Jjjag2099
The twin scroll by it self on a proper full divided exhaust manifold like the early DTS manifold without the EGR thing in the bottom will actually make the turbine more effective by 10 to 15% compared to the same AR sized single volute housing. So you will see slightly better spool from pulse effect but more you will see more drive which in turn will move your pr point across the compressor map which is more volume, so more importantly more density, so more oxygen for the same silly boost pressure. ( Remember boost is not a measure of how good a turbo is) But to see the full effect of that 10 to 15% we need good swirl flowing heads and all the other induction crap attached to the intake side of the head. For this .80 twin scroll which has a larger volute size than the .64 open volute we are behind the 8 ball for early spool, which gives us a faster higher torque curve. My early testing of a .85 twin scroll on a efr7163 on a STD manifold with the big hole in the bottom spooled slightly slower than the 6758 .64 housing. But still made more torque slightly later in the rpm range for the same IP same fuel. And a bit better with pin adjustments. The efr6758 .80 twin scroll on a STD GU manifold with the big hole spooled the same as the 6758 .64 same pump same fuel, same peak torque but 7 more rwkws at 3800 rpm with 1 extra AFR points and .3 points less EMP:IMP. This next project i am working on is to use a proper full divided manifold to get that extra pulse. So to answer your question yes a QSV like the one pictured above on a proper divided manifold with the .80 twin scroll will generate a lot more early spool and obviously more torque peak in theory. Most QSV are designed for open manifolds so their effect is a lot less due to no pulse. On the other side of the coin if we can charge as much boost as a turbo can generate before camshaft effective rpm point then yes we will see more torque. Holding torque and power in the upper rpm is a issue if EMP gets too far above 1.6 ratio. But then again there are quite a few turbos doing good power with 3 and 4 EMP:IMP at 3800 rpm if facebook crap is anything to go by.
@OldMav . Sorry, I am a bit of a pedant. I'm in the process of ordering a 6758 but keep swinging between the T25 .64 and T4 .8 twin scroll. On reading again many posts, am I right in thinking you have changed your views with time and experience and now favour the T4 for a fully divided manifold? Have I misunderstood. (I sometimes do you know lol).