im building a b20vtec, and i want to get about 350-400whp out of it, how big injectors would i need to do this, would 450s be big enough, and also i was reading some things and i was wondering what the difference in saturated and nonsatureated injectors was and what it dose for the car?

 

450cc injectors are only good for around 300 HP. 550's are good for about 350 and 650's are good for about 400 HP. Peak and hold injectors usually need resistors or a resistor box to be hooked up to your ECU. Saturated injectors dont need resistors.

 

Its really hard to judge... There are just too many factors that come into play... Things like torque, horsepower, BSFC, fuel pressure, etc....

My LS has a higher BSFC than a vtec motor, but I also run pretty high fuel pressure, so I am able to make right around 400whp with 580cc injectors (although they are at like 90% duty cycle with 70psi base fuel pressure)

I always reccomend going a little larger so there is room to play with, and also room for error... Besides the fact, most injectors like to run around 85% DC, which is where they seem to be most efficient... (even though to some an injector being "efficient" sounds kinda funny)

 

ok, well here's a stupid question, say i run like some 700cc injectors, just for insatnce but i only want to runn 300hp the only reason i have 700cc is so if i want to turn up the boost i know i have the injectors there to do it with...is this possible or do i need something else to go with the injectors to be able to do it?

 

Well your going to need to tune your ecu to work with the larger injectors obviously but going with a larger injector than is needed is fine..

 

I run RC 750's and make about 250 right now with my gt28rs. I was told that as long as your tuner and ECU can handle it, it is ok to do. Im using hondata and have had no problems thus far.