Every Badger 440 piston I have heard of has been a stock replacement mid 70's piston. And since that's how they said they built it, you will have about 7.8:1 or so compression. You will have to pull a head and measure to be sure. You remove a head, rotate the crank until that piston is at the top of its travel and use a caliper to measure how far down in the hole it is. Sounds to me you have a 99% chance of it being a mile in the hole 70's smogger piston. I would measure the overbore and order new pistons, have them installed on your rods and have the assy balanced. You will be miles ahead if you do this instead of using those low-cr pistons. They should just stop making those crappy low compression pistons but the mass rebuilders just keep buying them for their cheapie rebuilds. I would probably go with a set of KB237 pistons.