Rep Power: 0

Ok I'm trying to figure this out I think I know pretty much the conecpt but not exactly how it works. I.E. mr2 turbo 2.0 with 550cc injectors? It's a 2.0 liter engine 4 550cc injectors wouldn't that flood the engine and wouldn't you be getting very little fuel a lower rpms? I'm guessing you upgrade to bigger injectors to increase flow obvisouly but I guess the injectors never fully reach 550cc? So the advantage of bigger injectors would be what exactly? Better spray pattern and what else? So for all the q's but i'm quite stumped. mr2 is just an example you can explain with any other car. Thanks in advance.

 
Rep Power: 286

you need somethin like an apexi s-afc b4 you put new injectors in to control them, the ecu has no way of knowing theyre 550s

 
Rep Power: 0

OK! Here we go. 550cc injectors on a 2 liter engine doesn't matter. The Cybernation RSX kit (Stage II or III) uses 550cc, and that's a 2 liter engine. But anyway, onto the info. The flow of the injector (cc/min) is based on a specific static fuel pressure. So any injector can exceed it's flow rating (not saying that's good). But you can run a 350cc injector at 400cc/minute if you wanted.

Here's the deal though... it's all about flow. Spray pattern is important, for the purpose of equal distribution. A 240cc injector at 100% duty cycle at the certified standard pressure will flow 50% of the fuel that a 500cc injector at 100% duty cycle at the same pressure. However, you don't want to run any injector at 100% duty cycle. It'll burn out. You want an injector that matches the application, that doesn't have to run a high duty cycle to deliver the fuel. The larger the injector, the lower the duty cycle you need to provide the same amount of fuel as the smaller injector. You don't want too small of an injector. You want an injector that won't cause backpressure in the rail (causing the excess fuel you want in the engine to go back to the return line... or in a returnless system it doesn't even go anywhere) You want an injector that isn't too big. It will have issues spraying the correct amount of fuel if you don't have the pressure to back it up.

If you are talking about our cars, it's beyond just injectors. Larger injectors are worthless without a way to boost fuel pressure. I converted to a return fuel system. Fuel pump delivers more fuel, FPR regulates pressure, fuel computer alters duty cycle, injectors deliver, extra fuel returns.

 
Rep Power: 585

same here

 
Rep Power: 0

Boosted2k2 Thanks dude