If you look at how the two inlet pipes are plumbed into the front plenum, the air stream from both turbochargers points right at each other. Not efficient and optimum in my opinion.
When designing an i/cooler, one has to take into consideration how the charge air will be dispersed across the length of the core for optimum cooling efficiency. The idea is to get the charge air to spread across as much surface area of the core as possble, for best cooling effect from the ambient air going through the core.
If you look at the design of the C2T, RUF, Kokeln, BlownSixDesign, Protomotive i/coolers, all their inlet tanks are designed for best possible air dispersion across the core for optimum efficiency
I'm no fluid/air dynamics expert, but to me, that inlet tank design sux.
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition