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Well, i`m not gonna be a dick like everyone else, so i`ll try to break it down for you. We were all noobs once and as long a you want to learn you should get just as much respect as the "car gurus".

Okay, The "perfect" (stoichimetrically(sp)) a/f would be a 14.7:1 in theory. The problem is that not all of the fuel is always completely burned and such a ratio would run very hot anyway. At low rpm and low load operation this is not a problem though since not as much heat is produced and the fuel can be almost completely burned. This is why our ecu's run the car in Open Loop mode under such conditions. In open loop mode the ecu uses the reading from the front o2 sensor to maintain as close to a 14.7:1 a/f ratio for fuel economy and low emissions(since the fuel is being almost completely burned). It is called open loop because it is an open feedback loop. Under high load, high rpm operation the ecu switchs to closed loop mode in wich preset amounts of fuel are injected maintaining a predetermined a/f ratio. For natuarally aspired cars the optimal range is from 12.5:1 or 14:1 depending on the modifications, specific load/rpms and how aggressive the ignition timing is. For forced induction cars the optimal ratio is significantly richer ,like 10.5:1 to 12.5:1,(contains more fuel for the amount of air being introduced) since the air is heated from being compressed. The engine is running under a higher load and heat so the a/f cant be as lean (less fuel for the amot of air being introduced) because it is harder to make sure all the fuel is completely burned. If all the fuel isnt completely burned then you are effectively running a leaner a/f which, as it has already been establish, burns hotter and heats up the combustion chamber more. This exccesive heat is bad because it can cause the pistons to melt down, further stress other engine components such as rods, or cause a weakening of the cylinder wall itself among other things. The continued excessice heat in the combustion chamber can also lead to detonation if it is not dissapated fast enough. Detonation is the preignition on the a/f mixture before the piston/rod has made it all the way up in the compression stroke. Since we have 4cyl 4 stroke engines you would essentially have 3 pistons/rods all trying to come down at the same time. One going down in its proper power stroke, one coming down in its proper intake stroke, and one coming down in a power stroke while it should be in a compression stroke. This can cause piston, rod or crankshaft failure and can lead to such wonderful things a a piton throuh the head, a riston/rod in the oil pan, or a hole in the side of the block among other things. To much ignition timing, in other words cause the spark plugs to spark to far from TDC (top dead center, the pistons is at the top of its stroke), can also cause detontion. But as you can see running lean is a very bad, and potentiolly costly condition. You will actually make more power though(theoretically) right until your engine blows. The trick is finding a happy medium, one in which the a/f is rich enough not to cause damage but lean enough to make power. This all varys depending on your setup( ie turbo or not, and the size of the turbo). A good tuner will be able to design a fuel and ignition map that is perfect for you setup as well as a good vtec point, revlimit, and proper cam timing.

No, bigger fuel injectors by themselves will not fix this problem. Since the ecu will not recognize the larger injectors it will leave the injector pulse( the time the injector sprays fuel into the manifold, usually measured in ms(miliseconds) the same and you will be injecting a much larger amount of fuel since the volume of the injectors is larger. The best way to introduce more fuel into the engine(esp ours) is lengthin the injector pulse through tuning. Tuning is important. since the a/f might need to be varied based on rpm. when the injectors are at 80-90% duty cycle(the maximum pecentage at which the injectors can run) it is a good idea to upgrade them and retune to compensate for the aditional volume of fuel that will be introduced through the larger injectors. When upgrading injectors remember to only use low impedence(sp?) injectors so you dont fry the ecu. Eventually you will aslo need to upgrade other fuel system componets such as the fuel pump when it nears its maximum duty cylce.

One more thing. The reason the CN kit tends to go lean is because the ecu does not compensate for the turbo building boost at partial thottle and continues to run in open loop mode which as said earlier can cause problem. The kpro(automatically switches to closed loop at a preset pressure) and the Gaurdian can resolve these issues though.
You can also just keep an eye on you boost guage and throttle position to make sure you are running the right fuel seetings. The SAFC included with the kit trick the ecu into running more fuel by thinking it is under more load. It has 2 fuel maps that engage based on throttle position. So if you understand how it works and keep an eye on what the car is doing you can prevent problems.

If you really want to run a turbo kit then i suggest you do a lot of reading and talk to some knowlegable people to learn as much as you can so you can run the kit safely.If you buy it right now i wouldnt suggest trying to install it yourself or even having it installed until you fully understand how it works so you wont run into any problems. If this seems like too much hassle for you and you still want to run forced induction you might want to consider the JRSC since it is a little more plug and play and you dont have to keep an eye on it as much and there is less maintinence. Sorry if i went into a rant or if i missed a few thing i`m kinda tired.
 
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