*
Disclaimer *
Anything written in this post is at your own risk! Me nor anyone else is responsible if somthing were to happen to any parts of your fuel system or any persons. This F.A.Q. is for the 7th gen. only. Other vehicles may be similar.
#1 What is a fuel system?
A fuel system consists of the parts needed to deliver and return or just to deliver fuel to your motor as needed.
#2 What parts are in a fuel system?
A basic fuel system consists of a fuel tank, a fuel pump, a fuel filter, a fuel pressure regulator, a fuel rail, and fuel injectors. They are all controlled by your cars computer called an E.C.U.
#3 How the 7th gen. fuel system works.
The fuel starts off in your fuel tank. The fuel is then sucked out by your fuel pump (((which on our model has a built in fuel pressure regulator to keep the pressure in the lines at a certaint psi)))and fed through fuel lines up to our fuel rail. The fuel in the rail is then distributed to each injector and each injector will then spray the needed amount of fuel into each cylinder. The fuel system stops here unless modified. No fuel is returned to our tank. The system on our vehicles is known as a returnless system. Meaning that the remaining fuel that we would normally have in the fuel rail will not be returned to the tank. Our system is also lower pressure than older models due to this factor.
#4 How much boost or nitrous can I run on my stock fuel system?
This has been a big question for a long time. We now have an understanding of what the limit is. Let's start with the nitrous.
NITROUS LIMIT: Anything up to a 50 shot will be fine. You can run a 75 shot max, which some people do. The motor may lean out a little bit, but not enough to cause any problems. Let me stress that nothing more than a 75 shot is safe in any way. Some one might be or have run a bigger shot than a 75, but I don't think anyone would recommend it. After a 75 shot the motor will lean out causeing the engine to cough and spuder. The fuel system at this point is maxed out and the motor is running super lean. Detonation and fuel shortage are common at this point.
TURBO LIMIT: Now this is what most people argue about. Some might even have different opinions from this post. We tested 3 different 7th gens. at our shop and the result was 3 to 4 psi. Some might be or have run more than this, but remember we are maxing out the injectors and are staying at a resonable stoich (((air/fuel ratio))). Otherwise like said with the nitrous, detonation and fuel shortage are likely therfore breaking stuff.
#5 What can i do to upgrade my fuel system?
This section is going t be the biggest. I will tell you what things you can upgrade in what order. I will also tell you two ways to upgrade each part depending if you are on a budget or not.
INJECTORS: Upgrading injectors is a must. Our stock injectors are known as 240cc with a capacity of 3 to 4 psi or 50 shot of nitrous. You can upgrade to a rsx injector which has a capacity of 320cc (((some members have had there injectors flowed and came up with results of up to 340cc on rsx injectors but this is the basic so you dont push limits and this is what we flowed them at))) These injectors are good for 8 to 12 psi max or 100 shot of nitrous max. You can order bigger injectors of any cc you need. RC engineering will custom make them for about 400 shipped. (((321-639-3288 ask for Junior))) Just upgrading the injectors will not be suficient. You will also need to upgrade the next part we talk about.
FUEL PUMP: Your stock fuel pump needs a little help. You can put a inline fuel pump to boost your fuel pressure or you can replace your stock one with a better one or completley get rid of your stock one and get a high pressure inline one. Anyone of these is sufficient for the amount of boost your stock internals will hold which is a whole different subject.
FUEL CELL: You can get rid of your stock fuel tank and mount this in your trunk or where your stock one is. This is for you serious people like me, but it is not neccesary at all. It makes it a lot easier to to a return line which is the next part.
RETURN LINE: This converts our fuel system to a return fuel system. You can either drill a hole in you fuel rail and add a bung for the return line to run back to your fuel tank or fuel cell. You can also have a custom fuel rail made.
FMU: An FMU works by upping your fuel pressure in your fuel system when it senses boost in your intake manifold. For example, you can set the adjustable ones anywhere from every 1 psi boost it ups the fuel 1 psi and they usually are adjustable up to every 1 psi of boost ups the fuel 20 psi. Set FMU's come with a preset setting that is somtimes interchangable. On a returnless system before the fuel line enters the fuel rail it is ran through the FMU then to the fuel rail. It holds the needed pressure in the fuel rail. On a return system the fuel line is ran through the fuel rail then through the FMU then back to the fuel tank. This keeps the fuel pressure up in the rail before it goes back to the tank. It has a vaccumm line ran off the intake manifold to read boost and vaccumm. If you have an FMU it is not neccessary to upgrade you fuel pressure regulator unless you dont have one of the options listed under fuel pumps.
FUEL FILTER: You do not need to upgrade your fuel filter unless you want a better one or you get rid of your stock fuel pump.
FUEL GAUGE: I highly recomend that you get a fuel gauge. This way you can adjust yourl fuel pressure with your FMU otherwise you will never know what the pressure is at.
FUEL CONTROLLER: You have a couple of options here. You can add a vafc2 to control the fuel (((to tune this clink on the links for help))). You can add a piggyback system (((Greddy E-Manage))) which wires into your stock computer also known as ECU to controll extra injectors. You weld one or two bungs about 4 to 6 inches away from the throttle body in the charge piping and they spray extra fuel in the motor when it is needed. This works but is still not 100%. The Greddy E-Manage can also trick your stock computer or add comands to the command list to control fuel which is better. The best way to go which is also the most expensive is to switch the whole computer completley to a S.D.S. (((Simple Digital System))) or another good stand alone system. This wires into your stock sensors and gets rid of your stock computer completley. With this you can program the whole range of fuel air, timming and everything, but a dyno is needed. A dyno is needed to properly tune any setup to a 100%
LINKS FOR HELPING HOOK UP OR TUNNING E-MANAGE AND VAFC 2:
E- MANAGE:
http://www.7thgencivic.com/forums/sh...light=e+manage
VAFC2:
http://www.7thgencivic.com/forums/sh...t=tunning+vafc
My name is Phillip but everyone calls me P.J. If you have any questions you can call me at (321)-403-7833. Or if you need a number to get a part. If I left anything out feel free to PM. me after I finish it. So we don't clog it all up by posting on here. I am just trying to help out the fellow 7th gener.
****The pictures below are used as a key to show what each part looks like for a user reference. The pictures are in the same order as they are talked about. Not all pictures below are the exact application for the 7th gen. civic.****
The 7thGen Fuel F.A.Q. 
