First off, your wheels will work perfectly for powersliding. Wide, hard wheels are easiest to control, although it might be a bit intense if the ground is rough.
Now, you asked about how to avoid wheelbite. I'm a serial wheelbite offender, but it shouldn't really be an issue for powerslides. Rather than turning hard, you want to engage the slide by getting weightless for a second by bending your knees and doing a subtle hop-motion while pushing the board in front of you and into position (especially with your back foot). At the same time, throw your shoulders frontside/backside. For hillbombing, you're obviously going fast, so return to a riding position before your weight comes back on, as you risk sticking and getting pitched (this is arguably radder though).
If you've ever snowboarded, it feels similar to how you carve and brake. For backside, you're on your toes, and for frontside you dig your heels in to avoid the board digging into the snow and yeeting your ass.