he...he...he...

I'll have a 2c go....
The following are from my latest engine model and assume a 12AFR is possible...by the sounds of it maybe not above 350rwhp (ie: if you're stacking)
These are rwhp numbers....and assume 20% tranny losses - so divide by 0.8 to get bhp.

stock.........................296
65pulley....................325 = +29
SCooler -10C AIT.......334 = + 9 (colder charge)
DCAI.........................341 = + 7
178crank...................360 = +19
Remove DCAI............352 = - 8

Now I'm using NW's 15"WG loss numbers for my intake gains with a 1psi at stock WOT across the throttle plate....and she's sucking in 600cfm stock.
I've been running and tuning this model for a couple of years now....maybe it needs an EC...;>)...sorry cant "calculate" that one - but sounds like a shop tune is the way to go.
For the 350rwhp - your stacked, pushing >20psi and got lots of other mods you're wanting, but you're also low 12's.

350's a nice number because it = 320kW bhp...your cousin, the SLK32's series numbers (minus the zero)....

so
65mm pulley (or 62)
Cold air - (don't right off the Killer chiller + maybe 2L add on tank to increase thermal mass) and a
DCAI
+ Tune and you're done....
enjoy it for the next 10 years....apart from the wavetrac and paddle shifters with TCU tune....;>)
and keep your eyes pealed for a S4 Kleemann SLK55 for sale with ~600bhp - but my next fast car by then will most probably be electric...