The one I use, is called Dyno Sim6.
With it, you can use the actual cfm head flow numbers and the actual Comp Cam, lobe profiles. It has a PDF file of all of CC lobes. You pick your lobe and inter the lobe number, into the sim. All the cam events can be changed.
The exhaust systems can also be changed but, you can't specify the tube sizes, stepped primary's or a merge collectors. You pick the system type (manifold, triY, large tubes or small) then you pick the torque range and it out puts the tube and length.
I've been able to match posted dyno pulls but, the rpm may be off 100 rpm, both HP & TQ and the actual torque can be off as much as 30 lb ft, on a 600 lb ft, dyno reading.
It's sensitive enough to add or subtract HP & TQ for rod to stroke ratio's.
You can check some the input/output screens in the FE vs 460 thread.
I also use Pipe Max but, you can't use actual lobe profiles or actual head flow, just max flow but, it will go a little beyond your head flow and tell you what you need, in both head flow and cam profile, then you have to find a profile that will match. BUT, you can't change it's cam numbers, even though you input your own. It tells you how wrong you are.
I use it to compare the Sim6 and to get basic, header info and try to find a header that matches, as close as possible.
The basic HP range (max HP & TQ), seems to be good on both but, I don't use it for actual HP & TQ. I look for areas to improve performance, such as low end streetability and highest average HP & TQ in the rpm range, I'm interested in.
I do antique tractor pulls, also and use it for 1000 - 2700 rpm engine improvements, too.