If traction isn't a problem, in other words, you are not spinning, then your carb set-up and/or converter are wrong. It would be possible to be well into the 11's or even 10's with a properly tuned combo like yours - footbraking! But there are a lot of possible variables holding the car back. Personally I think the carb is too big and you could use more gear. I don't use a trans brake and don't know what your converter is doing anyway. But weight isn't what holding you back. However, moving the battery from the front to the rear will help the car be more consistent on a marginal track. The Cal-Tracs should also be readjusted according to instructions anytime anything is done with the weight.