What RPM should I shift at?

Did several runs at the Mopar Nats last weekend. Tried a little of what I read here and found the the best MPH was shifting around 5700 RPM. ET times were also a little better. Ran fairly consistent times of a 14.68. Guess it's ok for a 100% stock car. I am now on the fence about just dropping the coin and ordering an engine from Blueprint. Thanks for everyones input!!!

Sounds about right, nice job!
Back in 1972 I made my first ever lap down the track in a 69 340 GTS, my first car. Bought it for 1200.
3.55 gear and cheapy headers. Went 14.23@99