The ve will hold boost just fine tuned right. Even with the 12lb spring in your external gated t28, you will have no issues if tuned right. That will put you at around 300 or so whp, still have good gas mileage and have a responsive setup. Why would you bother to go external gate and run 6psi? I think the 12 psi external gate setup may even yield more than 300 whp just because of the external gate. If you have 93 octane, throw that 6lb spring in the garage somewhere and forget about it, such a waste of the turbo, the intercooler and the external gate. Don't worry about throwing rods out or any of this nonsense i am hearing about the ve. I have seen stock ve's holding more boost than we are talking about here for a long time and a long time ago, all while making amazing numbers on even old school turbos. This is not new stuff. The external gate should help keep the temps down and since you won't run more than 12psi, the turbo u have is perfect. Tuning tuning tuning. Boost the VE, tune it and run the 12psi spring and don't look back. Stop with this 6psi nonsense and the need to swap bottom ends. We are talking minimum boost here with and intercooler, a tuneable ecu and an external gate.
Drew