Need advice for slowing my car down consistently.

**Update**

Just in case anyone wants to know how to go slower....((crickets chirping)).....And now that no one is listening...:D...I've gotten closer to getting my car into the 12 consistently. This is where it sits now:

I added as much weight to the car as possible (safely). I removed the secondaries on the carb (now its a 2 barrel), backed the timing off 10 degrees (25° total currently), and I'm short shifting at 5500 RPM (I normally shift at 6500). This combo has slowed the car a little over a second.

This has gotten me close...Monday I raced it like this and lifted at the 1000 foot marker to run 12.05. Looking at the incrementals, I think this would have been an 11.87 pass if I ran it out...so, I'll probably pull a little more timing and call it good.