Hellion will be releasing a new TT kit for the 03/04 cobra that gives you the option of using it with the blower or without the blower.
In their testing sessions, they had the stock Eaton on the car with stock pulley(8psi) and the turbos at 26psi. In total, the car saw 44 psi after the Eaton and made 1200hp 1000lbs on stock motor(with fuel upgrades)
They continued to up the boost till at around 65psi the heads lifted.
The kit will be standard 57mm turbos, or optional twin 76mm turbos.