what is the next "step" up in injector size?
thanks a lot guys, your awesome i'm just going to leave them alone, probably don't need them as i have learned, and probably don't want them now lol thanks a lot, maybe the fuel pump though later
Champion
Joined: Aug 2010
Posts: 2,697
Likes: 3
From: Cape Carteret NC
I've got a fairly decent grasp on the workings, it's just that step being so steep between the gears that I found surprising.. that's pretty crazy..
fwiw- I tuned my engine, at great effort and through a huge learning curve, to effectively use 24# injectors when OE calls for 21#.. now, given, the OE 21# deliver a bit over 24# due to rail pressure, but the 24# are capable of delivering almost 27# using the same scale..
the duty cycle on the ones I am using is silly small.. this is good for my purposes, though- as I send true cold/isolated air to that thing.. I need the wider parameter at times.. I basically deliver the same volume of fuel through much shorter duration of squirt- and I altered the fuel sync to spray at the most advantageous time.. (in my case, retarded 4*)
it's a long story, but suffice it to say this, then I'll slowly back away from the topic:
most injectors are rated at 43.5psi.. my rail is 49psi... i deliver more than rated.. you would think that two injectors both rated the same would have the same rate of increasing flow as pressure increases, but they don't.. I learned this the hard way.. one may deliver WAY more than the other under circumstances outside of their design.. because of this, as well as other just as tricky factors, injectors are a messy subject that should be left alone unless you're prepared to engage it.. to engage it, you've gotta be able to sniff the a/f and log it.. and be capable of tuning/scripting the fuel tables..
it's tricky business..
fwiw- I tuned my engine, at great effort and through a huge learning curve, to effectively use 24# injectors when OE calls for 21#.. now, given, the OE 21# deliver a bit over 24# due to rail pressure, but the 24# are capable of delivering almost 27# using the same scale..
the duty cycle on the ones I am using is silly small.. this is good for my purposes, though- as I send true cold/isolated air to that thing.. I need the wider parameter at times.. I basically deliver the same volume of fuel through much shorter duration of squirt- and I altered the fuel sync to spray at the most advantageous time.. (in my case, retarded 4*)
it's a long story, but suffice it to say this, then I'll slowly back away from the topic:
most injectors are rated at 43.5psi.. my rail is 49psi... i deliver more than rated.. you would think that two injectors both rated the same would have the same rate of increasing flow as pressure increases, but they don't.. I learned this the hard way.. one may deliver WAY more than the other under circumstances outside of their design.. because of this, as well as other just as tricky factors, injectors are a messy subject that should be left alone unless you're prepared to engage it.. to engage it, you've gotta be able to sniff the a/f and log it.. and be capable of tuning/scripting the fuel tables..
it's tricky business..
Champion
Joined: Aug 2006
Posts: 4,489
Likes: 4
From: New Jersey
Agreed, but there are programs out there that are much more user friendly than having to code the fuel tables by hand... there are piggy back options as well.. all just depends on how much $ and time you want to spend...
I don't see a need for new injectors unless you go to a boost application. Otherwise, the fuel pump and adjustable pressure regulator will be all you need. Even on a bored out motor. Dodge does a really good job of supplying a top notch stock injector that can handle all of your non-boosted performance needs.
