Aero upgrades will be available - measurable down force in the real world is yet to be tested, but let me assure you - it is far, far greater than the current ones (which, whether you choose to believe it or not, DO provide down force and settle the car down a lot at high speeds
)
I'm not about to put any suspension geometry details on a public internet chat forum - that's commercial suicide. We don't give that out to
anyone which is part of the reason why there isn't anything like an Atom... We are more than happy to give out Setup advice, to change your camber etc, but not how the car works!
The Cup Car was never tested for torsional rigidity. However the Atom 4 has a 15% over the Atom 3.5. There is a difficult line between stiffness and compliance. too stiff and the car wold feel horrendous on the road, to soft and it would be wallowy on a race track.
I also don't see the obsession with comparing a standard 4 to a Cup Car or 3.5R... Comparisons need to be like for like really.
So:
A standard 4 is faster than a standard 3.
A standard power 4 with big brakes, bilstein adj shocks and a couple of other small items that you may or may not want is faster than a 3.5 310 with similar spec.
A standard power 4 with the above and some other nice-ities, wheels maybe, ohlins shocks, etc etc is
probably faster on the road than a 3.5R. However - it being a road, there has been no racing!
A 3.5R vs a std 4 with adj dampers, wheels etc etc on track hasn't been tested. I suspect they would be similar. A big bore 3.5R might be a different story. who knows!
A 4R with all the trick bits on it (wings, carbon wheels, carbon panels - essentially the '4' version of the '3') will be much, much faster round a track than a 3.5R. (however this is yet to be manufactured)
My simple understanding of BHP vs Torque:
BHP is product of torque and revs.
so actually BHP doesn't really matter. As torque is measure of how much force something turns with - after all, we use a torque wrench to do up nuts and bolts to the correct tightness, not a BHP wrench
although, a BHP wrench does sound handy?