Looking for info on how the upstream MAP sensor before the SC affects mapping.

The described application is for a dedicated autox r53. stock ecm with shark injector flash. still a stock r53 engine. I'm not going to aftermarket ECU until a get a race engine built. over boosted.

So the normal setup air plumbing sequence is:
air filter, 1st Temp sensor, (Cam Breather Recirculate), throttle body, 1st MAP sensor, (vacuum to Brake booster), supercharger, Intercooler, Bypass valve back to S/C inlet, Manifold, 2nd T-MAP sensor.

Problems I have with this setup for autocross in Prepared class:
-intercooler heat saturates when the car is idling in queue.
-the bypass valve, doesn't always close tight and looses some boost.
- having the throttle way down stream from the Manifold seems like a bad idea for throttle response.
-For the class rules I have to put a 45mm dia restrictor plate within 3.5" upstream from the supercharger. this would be after the throttle body in the normal plumbing.

So I'm replumbing and have 3 ideas. all 3 include a catch can on the cam breather (sick of blowing oil into the intake. I have huge brakes on a 1900lb car so I'm deleting the brake booster and won't need that vacuum tap. getting rid of the air box and CAI, moving the cone intake to the headlight opening. which puts it a a straight shot to the s/c, and I'm ditching the bypass -recirculate valve for a BOV.

implementation 1:
straight 2.5" pipe velocity stack to 45mm restrictor plate(3.5" to s/c)
step up to throttle body,
adapter plate to s/c inlet with tap for 1st MAP-sensor
replace bypass valve with blow off valve.

good: all the sensors are in the same order with respect to TB, oem plumbing order should work pretty much normal.

bad: the TB is 2.75" and I have only 4" to fit 1/2" long restrictor, TB, tap for MAP, tap for BOV vacuum line, and flare-out adapter to Inlet. I also suspect the the TB will not clearance the Radiator.

implementation 2:
straight 2.5" pipe with taps for 1st Map sensor and temp sensor.
velocity stack into 45mm restrictor plate.
3.5" long flare-out to match s//c inlet.
intercooler.
custom tubing with BOV
throttle body (same ID as manifold inlet, different bolt pattern)
3/8" adapter plate to manifold.
vacuum line to BOV from manifold.

good: the TB is right on the manifold for better response.
the restrictor plate flares out the the s/c inlet smoothly over 3.5". So it should only have a slight restriction if any.
the s/c is always pumping air, even when the throttle is closed, so when the throttle opens there is already charged air at the TB

bad: where to put the 1st MAP sensor? I understand it needs to be before the s/c. But does it matter the it will not be after the T/B and won't likely see vacuum as it di in the oem setup.

Implementation 3:
straight pipe to TB.
1st Map Sensor, velocity stack to restictor plate
flare up to s/c.
BOV after intercooler.

good: probably the easiest to build.
bad: 45mm restrictor plate comes after 61mm throttle body

Summary: implementation 1 keeps all the plumbing and sensors in the same order as oem, but the restrictor-throttlebody- interface- etc is going to be a PITA to build.
implementation 2 is the most radical in change but I feel it provides the most performance enhancement. My concern is that the 1st MAP sensor will goof up fuel mapping, or trigger a limp mode.
implementation 3 is basically oem plumbing with the restrictor plate. I think it will be a terrible idea to have a 45mm restrictor plate after a 61mm throttle body.

I'm leaning towards implementation 2, having the TB on the manifold just seems like the right thing for performance. I don't want to build a bunch of plumbing only to find out that the car won't run with the 1st MAP sensor ahead of the TB. My Bently book doesn't whow the 1st MAP sensor being an input on the ECM, so I suspect it is just there for OBD-II data. ie it doesn't directly influence fuel mapping (that is determined by the T-MAP on the manifold), but it could trigger a limp mode or something wacky.

additionally does anyone have any good reasons not to use a BOV. v/s the open - recirculate- vacuum valve system.

thanks,
Yarko