93 octane on a Mustang Dyno with the Killer B headers and full bolt ons will yield about 380. It's 10whp for every psi of boost so the Dom 1.5 drops off efficiency after about 24-25psi so 400whp is quite doable.
Get the 10cm housing, Killer B header makes it spool very nicely, it keeps EGT's down a bit.
Also consider at the very least a full driveline bushing upgrade from motor, transmission mounts, pitch stop etc all the way back to the rear diff. The extra power will need this upgrade or you might start to risk breaking things.
What are you trying to say here?
10whp/psi is linear.
"Dom 1.5 drops off efficiency after about 24-25psi" is not linear
Best I can come up with is that a 1.5XT could do 400 at over 40psi since 10whp/psi and add more for the loss in efficiency.
Nah. that doesn't work at all. 360 is normally at something near 22psi no?
So:It's not linear, it's just an approximation. 377 @ 21.6psi is quite possible on a heartbreaker dyno using good ELH like the Killer B. There are another 4psi there so exceeding 400whp especially with a good set of ELH like the Killer B and a moderately aggressive tune is quite possible. PM me with your email.
y = mx+b or whp = 10*PSI whp/psi + C
Y = whp = 377
m = whp/psi = 10
b = C = 161 (in units of whp)
10wph/psi*(21.6+4)psi + 161whp = 417whp