I power brake a bit but do not look at the tach. I have a canned tune from Dennis - Tasca Mod Shop. His tunes are safe and will pass emissions. My car shifts around 6600 RPM - I do not really watch the tach very often. I heat up the stock tires on dry track until they smoke and then stage. I am running 113 MPH as well. I run Shell 93 octane with no additives. Race wt. with driver is 3920 - stock Brembo wheels/tires all around. I am impressed with how well the stock tires hooked with the 3:73 gears.
Thanks for the info...what your doing is obviously working...i need to look into my 1st to second gear shift points...i think its short shifting...
Let me know if you beat your current best-