Hello all.
I am after some answers to the follow questions hopefully some one may have the answers.
I have been basing my calculations on the following information a 1oo hp shot of nitrous consumes 1.2 lbs of nitrous every 10 seconds has this any basis in fact?
As stated in my response to your other post, I believe that is much too high but I'll have to check my records to be sure. Having said that, there isn't really any point in concerning yourself about this, as you are "stuck" with the limitations you've mentioned, so you need to address your efforts to the factors I've mentioned in my other response.

I,m doing landspeed racing and need to run the nitrous system for up to 60 seconds each run that's over 3 miles and I can only carry 10 lbs of nitrous ( motorcycle space limited) need to supply an additional 140 hp via the nitrous system on top of N/A power, my caculations based on the above figures indicate a rate of 1.68 lbs every 10 seconds, so 10 lbs won't quite make 60 seconds, but I have not taken into account pressure drop or any savings using a ramp up to max power of 10 seconds if in fact there is a saving?
I've covered the usage rate looking too high to me but you seem to have overlooked the fact, that if you have 10 lbs of nitrous, you won't be able to get it all out in LIQUID form, so you'll only be able to USE, in the region of 7.5 lbs. and that's without addressing the pressure drop issue.

The temp of the nitrous will be aprox 100deg F , using 2x 5 lb NX bottles standard valve.
NOT A GOOD IDEA!!!! Luckily I can help you improve them but as they are from the factory, you will struggle to get ALL the liquid out and you will almost certainly suffer from a more rapid drop in pressure, depending on exactly which bottles you have.

using a won / nx hybrid system ,braided line to pulsoid
STANDARD braided hose will cause a SEVERE reduction in efficiency, unless the bottles are mounted appropriately. IF OUR nylon would do the job (flow enough [which depends on length required] and strong enough [at such hihh temps] both of which are unknowns), you would get a MUCH more efficient usage and if that's not an option, we can supply you with a CUSTOM braided hose that will be a close second option and still MUCH better than STANDARD braided. Both these options will work optimally no matter how the bottles are mounted.

then nylon line to nozzels metering jets at nozzels.
Locating metering jets at the nozzles is another factor, that has a TERRIBLY ADVERSE effect on efficiency, so you'd be MUCH better to switch to the UNIQUE WON technique of locating the metering jets at the Pulsoid outlets.

Are my calculations valid ? and if not how do I calculate the amount of nitrous used per second in my case of 140 hp.
Does ramping up the power over time extend the range of the nitrous ? and if so by how much, in my case a ramp rate of 10 seconds from 30% to 100%
Yes it does but again there is no 'specific' answer, as it depends on how long you set the build time at and even then it's not easy to calculate the exact amount.
However, going back to the REAL CORE of your situation, NONE of the concerns you've expressed are of any real concern, as you can't alter those, because they are fixed factors that are essential to reach your goal.
CONSISTENCY OF PRESSURE & MAXIMISING EFFICIENCY, using ALL the methods I've mentioned above and others I can suggest after I've seen your installation, are the ONLY things you can change, to improve your chances of success.

cheers