I'll just say, without disrespect to anyone else ...... You do NOT need to start buying a bunch of new parts and throw them at it to go faster than 9.1 @ 78 mph. Let's forget what's under the hood for a minute and look at the rest of the car.
- A-body with 4.56 gears, 3000 stall
That alone sets up basically a stock 318 4bbl to about run those numbers. This is why I would not start ordering new converters, or swapping anything. Yes, probably there are better pieces, but certainly not needed to go faster than 9.1. Just work with what you got and dissect it all. You'll be in the deep 7's. That's my take.