PUZZLER!!! My new motors a dog! what did I miss?

Say with .030 pistons at zero deck, the Scr Should be a tic under 10/1.This is how I got that; swept(CV) is 748cc, head chamber, plus gasket, plus eyebrows,(cv) = about 84cc.
Scr =(CV+ cv) /cv ; Scr = (748+ 84)/84 = 9.90. That's a pretty good number.

The 262 voodoo when installed at 108LDa should have an ICA of59*. Plugging that into the Wallace calculator shows a Dcr of 8.23(very good) and cylinder pressure of 165 psi. Since your pressure seems to be down, I would get a second opinion and if still low, likely the cam timing is off, or erroneous data has been given or assumed. You know the saying "garbage in/garbage out"

If the cam-timing is right that motor should smoke the tires with 3.55s, and 275s, right through first and most of second, on the street. Mine did with a Hughes HE2330cam, and Eddies.
You didnt mention, or maybe I missed it, what tranny/TC are you running?Not that it's a big deal with that size of cam. Mine was just dump the clutch and drive away. That size cam makes tons of torque down low. It would break the tires loose at any speed below 5000 in 2nd gear. I absolutely loved that cam!