Nitrous tuning advice

[QDRHRSE]

I just started racing a new combo that is basically a nitrous only set up- meaning that if the bottle is empty I don't race. I've never used nitrous this way and I don't know how to tune the car. I've only used small dry kits for occasional bursts but not for strict racing.

I'm running a NX wet unit and I have it jetted as low as it goes for right now. I'm worried about leaning out the motor. Can somebody give me a recommended way to test and tune it because I want to run a lot more. I locked out the timing at 26 degrees and run 42lb of fp (hose off). Does anybody have a more scientific way of setting it up?

I've made quite a few passes. I check the plugs after every pass and they look like I just put them in with the exception of the electrodes beind a little blue in color- but they look brand new. Is this good or bad. I'm used to seeing the plugs black, brown, or white. I can't read em if they always look new with a tinge of blue. I'm not a begginer so this is killing me! I need Jedi Nitrous Master help? So please, Yoda, if your out there give me some pointers.

 

[notchback]

well i raced w/ nitrous for about 2 years...in cali and michigan both.
so i'm pretty familiar w/ temps and humidity.
100 hp w/ base timing is good to start....i would retard about 2* for every 50 hp after that...but read the plugs...blue i wouldn't worry...when they start to melt definitely back off..do you use a fp guage?? that you can see when you race? ..it should spike to about 80 psi when on it...i wouldn't run w/ no vac hose...you'll just pack up when idling, if you can't the fp you need , you need to back off til you can..no vac won't get you any more fp than you would get anyway...just spikes it.
now the numbers i gave are for really warm to hot weather...in michigan springtime..low humidity and about 70*..i caould spray 100 shot at 12* and even accidentally squirted at 14* w/ no problems at all.
when i jetted for diff settings, i always plus'ed 1 on the fuel and minus 1 on the juice.
alot of guys said it was a waste....but it ran well and gave me a nice comfort zone.
and thats just my 2 cents. btw look at getting a window switch if you haven't already.

 

[QDRHRSE]

Thanks. Thats a good start. I do run with the vacuum line on the regulator- I just meant that I set it at 42. Window switch? You mean a purge line? I've got one already. I like the running the unit rich idea. Thanks!

 

[QDRHRSE]

OK. Found out what you meant by window switch. Tanks.