necrocannibal

iTrader: (5)

I was thinking about this the other day and Ive been wondering ever since. The kit is kind of a Frankenstein kit that I put together. The fuel soenoid is a NX solenoid. The nitrous solenoid is a Zex solenoid capable of flowing a 500 shot. The purge solenoid is NOS but doesnt come into play. The bottle is a NOS 10# bottle. Im using a TNT Power Ring and Zex pills., which are supposed to be the same as NX. Now I looked at a calculator on line that gave me pill settings for particular shots and it gives flywheel and wheel horsepower so I used the wheel horsepower calculations.


This is a link to the calculator I used. http://www.robietherobot.com/NitrousJetCalculator.htm


Using this calculator I came up with .073 on the nitrous side and .058 on the fuel side. (Im using a stand alone fuel system @ 10 psi) This should be 240 horsepower to the flywheel and 204 horsepower to the wheels. For some reason though I got around 180 horsepower to the wheels. I have attached my dyno to look at because my A/F was almost perfect on the nitrous runs and I dont understand why I would only gain 180 horsepower on a 200 shot. Any help would be appreciated.

Race Car Driver

Tuning would be the first place to look. For example, a fat 200 shot will not make as much power as a well tuned 200 shot.

necrocannibal

iTrader: (5)

Is my A/F not almost perfect? I thought right about 12 : 1 was perfect if not infact a tad lean.

NXJeremy

What nozzles are you using in the power ring? All of the miss matched parts could have something to do with it. I say this because not all parts flow the same amount (bottle valve, solenoids, nozzle, etc.).

Robert56

iTrader: (2)

I agree with what's been said. in addition, jet size equals this hp is just a general guide. There are so many variables that come into play, some guys will hit a jet=hp right on the next guy wont. That's why a tune is good idea and jet it for what ever size hit you want. If it was my set-up I would fatten it up a bit.
Robert

necrocannibal

iTrader: (5)

The nozzles are TNT nozzles as well, sorry about that. Im only using one nozzle right now.




So should I increase my jets sizes to get my desired numbers? Or is this not a good idea? Also you aid to fatten it up some is 12 : 1 too lean for a nitrous car? I thought it was about perfect. Once again thanks for the help.

calongo_SS

iTrader: (7)

I'd make the A/F around 11.5 or a tad fatter, that's what I'm shooting for anyway.

NXJeremy

Going by the information I have, a .073" nitrous jet is good for 175rwhp with our single nozzle systems. Again, that number is going to be different since you are using mixed parts. Getting 180rwhp sounds pretty good by the info I am looking at.

The a/f is different from car to car, and it's what you feel comfortable running. A lot of people feel comfortable running at 11 to 11.5:1, I ran my car at 12:1 and never thought twice about it. I, along with the other techs here, usually suggest running 12:1.

Nitro Dave's Nitrous Outlet

iTrader: (25)

The air fuel is fine.We tune our cars at 11.8 to 12.1 maybe 12.5 at the leanest.

To gain a 180 on a 200 is not bad.As stated above the frankinstine parts play a big role.Every company flows there parts for certain jetting.If you want the true 200 just go up in jetting.Make sure the air fuel stays the same.When you get to where you want stop.Those jet charts can get you close but in some applications they are not all that exact.
Dave

SDB

iTrader: (7)

a litle fatter AF ratio would mean maybe 15 less rwhp but usually more torque. Safer too.

Nitro Dave's Nitrous Outlet

iTrader: (25)

Keep in mind this when tuning your car.

Running rich will make more torque than running leaner.However if you get it to rich it can hurt your times not to mention washing your cylinder walls if way to rich.

Here is why to rich can slow you down.Through out your run the bottle pressure will drop regardless on a full bottle or half full.Obviously the half full bottle will have a larger drop.When the pressure drops the system will go even richer.So what will hapen is that you will have alot of torque out of the hole and your 60 foot will be great but then you will start nosing down and slowing down on the rest of the pass.
Dave

calongo_SS

iTrader: (7)

What would you say is an optimal a/f on spray? I'm still trying to learn...

NXJeremy

12:1 is a good middle ground because like Dave said the car is going to getting richer as you make a pass. So by tuning it to 12:1 you aren't running it too lean and it won't go too rich as you make a pass.

Race Car Driver

We spray a 140 direct port shot on our 622 bbc and the a/f ratio is in the 12s during the 5 seconds of spray and ends the run around 13.2 while on the motor. For a street car, as Dave said, anywhere between 11.5 and 12.5 on the NO2 would be common.

As a general theory, there is a direct correlation between higher a/f ratios and higher hp until a/f ratios reach somewhere above ~13.8:1 and then the inverse is true.

Patrick G

iTrader: (14)

In my LS1 experience, a .073 nitrous jet always gave me around 175 rwhp (NX single nozzle).

Robert56

iTrader: (2)

I don't disagree with anything that's been said. I have my ratio at 11.7, which is a little safer than 12 +. Now if I was running a full forged bottom end then I would probably lean it out. I also run dry 200 and the a/f dose not vary according to bottle press, so no need to have it leaner. Like what was said, It's what your comfortable with. I believe most of the common guys outside the shops, go closer to 11.5 for the safety factor.

necrocannibal

iTrader: (5)

Great info everyone I really appreciate all of it!! I know what was up now cause the jets I am using are supposed to be the same as NX jets and according to their charts .073 is a 175 shot. Now is there any place I can to get the proper jetting for a single and dual nozzle NX system?

Race Car Driver

Contact Nitrous Dave

NXJeremy

Necro- sent you a pm with all the jetting you wanted. Again, it is for our systems, so the hp numbers will more than likely be off +/-.

necrocannibal

iTrader: (5)

Thanks alot I appreciate it.