!!!!!!!!Major Correction!!!!!!!!!!!
I just discovered that my boost gauge was reading incorrectly. I had a SW gauge that only read to 10psi, and then I swapped it for a new gauge that reads to 20psi. Took the car out for a spin and discovered what I thought was 10psi was only 5psi. Bench tested new gauge, original gauge and a third borrowed gauge. The new and borrowed gauge read 5psi when my original reads 10psi. This would also explain why I have 12psi of fuel pressure (7psi base fuel pressure + Boost of 5psi = 12)
So, last year when I thought I had 7psi with the HO impeller, I only really had 3.5psi. When I swapped to the VR4 I thought I had 10-12psi I really am only making 6psi.
Please take note I am very sorry and embarrassed for the miss information, I did not discover this until a few minutes ago. I had no intention of misleading anyone.
FYI:
HO impeller @ 40k rpm was really about 3.5-4psi (7 crank pulley, 4.2 blower pulley, 5,500 engine RPM)
VR4 impeller @ 36K RPM was/is 6psi (same, but with 4.75 blower pulley) The 11.58 ET I ran earlier in the month was really with only 6psi and 25 degrees of timing. Evidently the 11.78 it ran last year was with 4psi and 30 degrees of timing.