I do get it. Thanks. Car has an AFR sensor and works just fine in the thin "air" up here. Given that octane values shift down about 0.5 point per thousand feet, my 93 octane sea level tune should be fine up here at 6000 feet on 91 octane gas. Probably why you can not even find 93 octane up here. My point is not to bash BAMA, they have been very nice every time I have spoken with them. N2O is essentially two things, properly applied, a 33% oxygen nitrogen ratio vs 20% for air and its butt cold, so higher density intake air when its fogging and it comes apart easily under combustion conditions. When I was a kid, we used to tune our old distrubutor cars at altitude on a long hill by just advancing the cap until they pinged under load and then backing them off a touch. My thing is that this altitude, along with the cars built in detonation sensor, provides a significant safety cushion in the use of nitrous and I just don't see the advantage of additional tuning at this altitude - maybe sealevel as well, I don't know. Show me some high altitude Stang data with nitrous and tunes and with nitrous alone and we can discuss this further.