That MPH you have with your auto LT1 is very, very high for your mods.
We have a 1994 Z28 auto in our club. With Mac headers and a cut-out, plus SLP CAI he ran a 13.7X @101.5. Then he added a LT4 Hot cam and some other bolt-ons (1LE intake elbow, gutted cat, tuning, 3000 stall ‘verter...