LSA is Lobe Separation Angle. Combined with long duration, tight LSA can cause a loss of low and midrange power with a supercharger, and turbo's too but for different reasons. Generally, you want the widest LSA you can get, which would be around 114° with the style cam you have without going custom.
However, before changing cams, I'd go for the tuning. There is usually a lot of power hiding there. Call ahead to be sure the dyno is using a wide-band AFR sensor, and if it's not a tailpipe clamp sensor, get a bung welded in your crossover pipe before you go. Get the dyno operator to print the Air:Fuel ratios as you make your pulls. Change carb settings between pulls if you can to correct, but at least be sure it's not running too lean or rich. If you have a couple hundred bucks laying around, definitely get a dedicated wide-band AFR (WBO2) setup to run in your car all the time. Cheap insurance and great for tweaking the tune. Richer than 12:1 can help suppress detonation, but will cost power doing it - especially if not needed.
Attach a vacuum gauge to a carb baseplate nipple that will read vacuum under the carb. If the vacuum gauge shows more than 2" vacuum at WOT and peak power, your carb is too small. Also be sure it's a properly modified carb for blowers with power valve manifold pressure referencing (tube from lower manifold to PV chamber) and the power valve selected properly (idle vacuum divided by two = power valve number).
Finally, your ignition timing usually holds the greatest power. The dyno operator should know how to make timing test pulls to zero-in on your MTBT (Minimum Timing for Best Torque). Best timing is NOT the most you can use without pinging. If you get det without reaching your MTBT, you need better fuel, water injection, intracooling, or a combination. Just retarding your timing will allow driving without det, but will cost power. A lot of power.
You've spent thousands getting to where you are - dyno tuning is a cheap way to unleash the ponies hiding in there and it's cheap insurance too. Have fun!