[ByronRACE]

But first, put a wideband commander (or similar) wideband oxygen sensor on the car so you can monitor air/fuel ratio.

Nitrous Oxide doesn't kill engines; detonation and lean air/fuel does.

So, pull about 1deg per 50-shot of timing advance to avoid detonation, and run the air/fuel ratio at about 11:1-11.5:1. Use a wideband oxygen sensor and gauge or logger to monitor/tune this in. Then, run as much nitrous as you want...being weary of knock and AFR...and it'll last a good long while as long as you don't exceed the capabilities of your hard parts like rods and pistons and crank.

A cast crank 460 with cast rods and forged pistons and 2-bolt mains can do 700+ without any worry what so ever. If you have hypereutectic pistons, be aware that any amount of detonation will likely shatter them. The ring lands go first usually. Hypereutectic pistons are less ductile than forged and don't tolerate shock as well. That doesn't mean you can't use them, it just means maybe pull 1.5-2deg per 50-shot instead to make absolutely sure you don't rattle the engine.

And as far as the "Why" comment, my answer is "Why even own a Cobra?" This has nothing to do with utility or reason, it has to do with desire. If you want it, do it. You only live once.

Byron