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Discussion Starter #1
What dictates the location of the nitrous nozzle on a single point system? Would it differ between wet and dry? It seems the most common location on the Focus is in the inlet tube before the throttle body. To me, that seems odd as why would you want the nitrous have to pass over that restriction? Especially on a wet system as the throttle could cause fuel to fall out of suspension.
 

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Dyno Queen
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ideal position is 6" before the throttle body. You need that distance for the nitrous and fuel to atomize so you get a fairly even distribution among the cylinders.
 

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Discussion Starter #3
ideal position is 6" before the throttle body. You need that distance for the nitrous and fuel to atomize so you get a fairly even distribution among the cylinders.
Help me out on this one. How does a longer path help distribution? If (for example) the #1 cylinder gets better air than #3, why does it matter where the stuff is introduced?

No doubting what you say, just not understanding the reason why.
 

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Dyno Queen
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The closer you spray the nitrous to the intake manifold, the less time it has to completely spread out in the air. It will follow the same path of where it came in and like much of the charge will go into 2 of the cylinders. The longer path allow for more time to spread out. Think food coloring in water.....

Obviously, the characteristics of the intake mani will, like you said, favor a cylinder or two. They will always get more of the charge, not much you can do about that aside from direct port. But with it a bit farther down stream, you can minimize that distribution problem.
 

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Discussion Starter #5
The closer you spray the nitrous to the intake manifold, the less time it has to completely spread out in the air. It will follow the same path of where it came in and like much of the charge will go into 2 of the cylinders. The longer path allow for more time to spread out. Think food coloring in water......
OK, I get it. It is not so much the distribution of the fuel in the nitrous, but the fuel and nitrous mixture into the 'normal' airflow. Cool. Thanks.
 

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Rich, I don't know much about the practical application of nitrous, but if you introduce it upstream it should disperse evenly throughout the air charge, so even if one cylinder is getting more "charge", it is getting the same amount of nitrous and fuel as all the others.
 

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Discussion Starter #7
Rich, I don't know much about the practical application of nitrous, but if you introduce it upstream it should disperse evenly throughout the air charge, so even if one cylinder is getting more "charge", it is getting the same amount of nitrous and fuel as all the others.
Yeah. I was confused because everything I had read talked about how distance was needed to ensure proper mixture and I ASSumed that meant the mixture of fuel and nitrous being introduced, not that mixture into the regular airstream. Since direct port kits cut down the distance before combustion drastically, my explanation didn't make sense. But, now I know. From what I have read, a 50hp shot should be safe and easy to do.
 

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Yeah, direct ports should be able to mix the air/fuel/nitrous because there is so much turbulence there. Plus, distribution port to port is much better.

Why are you asking? Planning on a "push to pass" button?
 

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Discussion Starter #9
Yeah, direct ports should be able to mix the air/fuel/nitrous because there is so much turbulence there. Plus, distribution port to port is much better.

Why are you asking? Planning on a "push to pass" button?
Actually, I was thinking that for hillclimbs and time trials, short duration power is not a liability due to the like duration of the events. Just toying with ideas. Nitrous is so much cheaper than boost, and unlike any other power mod I can come up with, leaves the daily driver aspect of the car completely untouched.
 

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Do they allow nitrous for hillclimbs and time trials?
 

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Discussion Starter #11
Do they allow nitrous for hillclimbs and time trials?
NASA CCR says that N2O is legal so long as the car has a fir system (odd as nitrous is not flamable, but whatever) and I have been unable to find any prohibition in the SCCA rules. I would run the car in SM if they allow Solo II classes or SPU in club racing classes.
 

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Holy crap...DFL lives. Haven't seen you post in awhile.

/off topic
 
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