what flywheel

If you are running a starter gear of 2.66 x 3.55 =9.44, or less, then your engine will want a heavy flywheel so you can get moving without stalling it.
If you are running a starter gear of 4.56 x 2.66=12.12, or more then you could run a lighter flywheel.
Between these two ends, namely 9.44 and 12.12,It would kindof depend, on the engine. If it has plenty of torque right off idle, then you could use the lightweight. If you have over-cammed it and the bottom sux, then you better stick with a heavier one.

This is based on my experience. You are of course,free to choose whichever,and see how it goes.

There are really only two reasons you use a lightweight; 1) is cuz you can,re the starter-gear, and 2) is cuz it takes less horsepower to spin up.
There is really only two reasons to use a heavy flywheel; 1) is cuz the engine needs it for take-off, and 2) it helps smooth a jumpy tune.
At the racetrack, a heavy flywheel can help get a little engine in a heavy chassis moving lickitysplit.
I prefer a heavy flywheel and a 10.97starter gear. With a mild street cam, it's a dump-it-and-go take-off.
The bigger flywheel also tames the power pulses when you drag the engine down to the stall-zone, cuz Billy-Bob is trying to have a conversation with you, outside the car, and you just really wanna go home.