Compound compresses the charge twice, we're talking about a sequential setup that doesn't suck ***.

 

Exactly, it's only compound in the lower rpm area when the large turbo doesn't restrict the small one and does need pre-spooling to be smooth when being transitioned into. Once the big one comes up to speed the small one gets totally bypassed and everything is efficient and lovely. 2k - 7k 20psi+ FTW.

 

The biggest reason this is not a viable solution for a gasoline powered vehicle is the PR's that it produces. It is easy to get 60psi out of that setup, and not uncommon to run 100psi+ As well as was mentioned it still only works over a very narrow power band. As even a full pulling cummins diesel still at most only turns 6000rpm and the boost threshold in that setup would be about 1500 - 1800rpm with use able boost not until 2200 - 2500rpm. Leaving you with a power band of about 3500rpm, or about the same as stock. In a street setup they can extend this power band a bit, but at the sacrifice of peak hp numbers.

 

Why would you connect the blower's output to the hotside of all things. That's retarded.

In a twincharged system you would run that to the COLD side of the turbo, thus helping to spin it quicker (you do know how a turbo works, right?).

The boosted charge (containing a much higher volume of air than aspirated) after the turbo then goes to the combustion chamber, where it comes out as as a much higher quantity of exhaust gases (-> pressure) that also help spin the turbo quicker.

 

truth, problem solved. Ford 2.3 guys have made 500hp with the 12cm housing and it spools up quick to boot.