Best rotator kit......

Whats the best 545-557 rotator kit? For a s/s mustang, Strip only

You need to give us your hp goals and rpm you want to turn. You can get a inexpensive cast kit, up to a high dollar billet kit. Or something in between.

Want to make 850 N/A and spray the hell out of it 3000LBS, and I'm not rich... lol

I'd suggest a forged crank and keep on top of the tune up. Scat makes a nice one. Without knowing what heads and fuel you will be using cannot recommend a specific kit. I'd also think about 4 bolt mains for the block.

As Steve said a 4340 crank with h beam rods with forged pistons. I have been having good luck with the Eagle assy with Mahle pistons. Just get the right valve reliefs and domes when you order.

Race gas and unsure of heads yet. Open to suggestions!