Acutely very little lag, but the motor they go in is so large I can stand in the cylinder at BDC quite comfortably, the piston it’s self is about 3’ diameter.
The BOV, is not really what you and I would normally call a BOV. It has a press relief to prevent explosion of the intake manifold, that relief is hydraulically opened when decelerating. The motor it’s self is almost always running at a constant speed. There is also no real WG, it’s just plumed with a small tube that bypasses the larger turbo and flow is balanced for a normal operating condition.
The setup it’s self is 1 turbo per cylinder and the motors can be built for 1 cylinder to I think as big as 12 (we don’t always get all the scrolls at once, this set I think is going on a 3 cylinder). The smaller turbo is hydraulically gated and is only used on start up, once the motor is fired and turning the smaller turbo is closed off and the larger one force feeds the motor. The 4th turbo in the pic, the medium size one, is actually for a V12 diesel generator with pistons about 8” in diameter…
Yes I’m sorry that my spelling sucks… And spell check dose nothing for homonyms…
On another note though, if you strapped them to Cosmo/Wanda and they could use them to turbo there magic, that could be some kick ass magic.