I have a similar setup, lm7, 224/228 tsp, 862's milled .040 with a competition valve job (im guessing around 10.15 ish compression) longtubes, tight 2800 converter and 4.10s and ran a 8.48 8th the other night on a 1.91 60' at 81mph. I feel like a little port work wouldve benefit quite a bit but my next stop is a better converter!