UPDATE:
WOW. Setup works very well. Spool / response with the VGT unit is INSANE.
Something like 1600rpm faster response vs my previous turbo (EFR 7670 t4 twin scroll)
Above 3500 the boost response with the VGT unit is instantaneous. Basically as fast as you can put your foot down.
At 1.3 bar the peak power is similar to the EFR unit, but with a
massive low end and torque advantage. Nearly 100ftlbs more peak.
Above 1.3 bar, the VGT unit basically runs out - no additional power to be gained. The EFR unit shines at the higher boost levels, and flows much more on the high end, but with a significant loss of low end and boost response.
The next steps will be to have the VGT turbo's compressor wheel upgraded. On the Boxster / Cayman this adds a little lag, but delivers far more flow up top - 600hp is possible (apparently)
Some notes on comparisons:
EFR 7670 dynos were on a 77 2.7 engine. The VGT dynos are on a 3.0 engine.
EFR 7670 dynos were done at sea level (Santa Cruz, CA). VGT dynos are at about 2600ft (North Idaho)
At sea level, the VGT unit would likely reach full power even faster, and deliver a bit more power.
At 1.3 bar. the VGT unit is clearly superior - even at higher boost the 7670's gains are small and only up top.
Overall, the stock VGT unit is absolutely fantastic for a street driven car. Porsche really knew what they were doing with this unit.
To get a little more power (400-450whp) a wheel upgrade is needed. I will test this next.
VGT 1.3 bar VS EFR 7670 1.3 bar:
VGT 1.3 bar VS EFR 7670 1.5-1.6 bar:
More to come soon.