I run a hotside TVS 900 that magnussen made for me as a replacement for my MP62 SOT kit. 10-12 PSI would be quite high for an AP1. I run a max blower speed pulley and that (on the 900) is a 6 psi pulley. You could get about 8-10 psi on the same max speed on an AP2. A TVS 1060 would be a great fit for what you want, but nobody makes them. The TVS13something is a bit on the large side.

I wish I could say more about it but have gone through a tuning nightmare after switching from Emanage to Haltech. Four trips to the tuner and it is not where I want it to be.

I just ordered a larger intercooler that should arrive at the end of the week and I hope to get into another tuner and get some things straightened out and I will post a sheet if I get one, but I don't know the tuners schedule yet.

Depending on what you want, you would probably come up short of 400 at the wheels on an AP2 TVS 900. It is quick though and fun to drive. I thought something was wrong because first was feeling sluggish and second was much better. The big problem is traction. Instant full torque in first makes it pretty useless with my cheap tires. I need to find stickier ones. I am not looking to be the speed king of Minnesota, but even at whatever power level I am making, it is far more than I can really use in traffic. I can only guess I am around 320-350 at the wheels in a 2800 pound car with max torque (~210) across the whole powerband. That is less than many cars here in the FI section, but the behavior of the powerband is different from a kit that makes more power but all at the top end. The max is lower but has more under the curve.

It all depends on what you want. You want what you want, but I would not let a hangup of a dyno sheet final figure be the deciding figure, just because a twin screw or roots are a different kind of power delivery that a centerfugal and the lower number can still be a whole lot of fun. I dont have 400hp but walked away from a new Mustang GT the other day fairly easily so it is not really slow at that power level.

You can still make huge numbers if you want, you just have to use larger, more expensive blowers, deal with cooling and fit and other issues. The TVS900 seems like a nice little unit, and is cheaper and smaller, but it will probably not get you to a "goal" figure of 400whp.