Two Injectors per Cylinder.

Randy N Connie

Registered User
What would I need electronical to get an extra injector per cylinder to fire and be tuned.

I was looking at the gt40 motor ,and was wondering if this dual injector per cylinder set up

Could be done to a SC motor using extra computer from a SC or just what it would take.

With this set up I would be able to keep a closer A/F ratio across the RPM range.

RANDY
 
Randy, I don't think an EEC Tuner or TwEECer piggybacked to your original EEC-IV system could accomodate that, somebody please correct me if I'm wrong. You would likely have to go with an aftermarket stand-alone system like Accel DFI, Anderson PMS, SpeedBrain, SDS, or something of that nature, a fully programmable system.


cheers
Ed N.
 
Randy you can get a piggyback injector driver that is boost activated..Therfore running a smaller injector under non boost applications...Years ago I did it with a stang..Dont recall who made teh driver though
 
What problem would you be trying to solve by using two injectors per cylinder? And where would you put the second ones? There is barely room for one per cylinder. Maybe I misunderstood something.

You can already get larger injectors up to 50lb, or much larger (160lb) if you switch to low-impedance and an aftermarket controller. But so far I haven't heard of anybody needing larger than 50lb, even the 11-sec crowd...
 
Fast N Ed: thanks for the names.

Thanks DAMON, Thats kinda what I may be looking for.I have been thinking
of changing, & adding more boost,So I beleive it will take smaller mist but a
wider volume band to get the A/F ratio. for the oxygen I may shove in a new
motor,at differrent RPMs that two injector sizes per cylinder could do better
than one large injector.

Rob, there is all kinds of room for more injectors.Ask Brian H. what he
could of done with more tunable wide band of fuel.
I just started to think about this so don't kick me in the teeth to fast.Give me
a week or so first.Then you can say I told you so.Some times it takes 1000
hair brained ideas to come up with one good one.:D

RANDY
 
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With the sheetmetal intake manifold I'm working on there might be enough room to mount 3 injectors per cylinder if you like.
I may be mistaken but I beleive those extra injector drivers only handle up to 2 injectors not 6, but I may be wrong about that.
I do know for sure that the stock comp will not be able to handle the extra injectors because the load on the driver transistors would lower to the point that too much current would flow through them thus burning them out. You would have to go to a stand alone comp system to do this Randy. Which is not a bad thing per say but the cost is up there. The last one I played with cost $1200.00 and that was 2-3 years ago, so they may be higher or they may have dropped in price.:)
 
That one can handle up to 8 injectors...Also teh reason for running dual injectors is simple...Better fuel atomization..Better gas miliage and better drivability..I miss anything? ..Oh and better tunability..You can drive around town qith 19lb's and then have an additional set of lest say 24lbs for the boost..Or vica versa or any combination ya like
 
Randy,

This may not help you, but this is my next nitrous mod. Adds fuel and nitrous to each cylinder



s08100NOS.jpg
 
DamonSlowpokeBaumann said:
That one can handle up to 8 injectors...Also teh reason for running dual injectors is simple...Better fuel atomization..Better gas miliage and better drivability..I miss anything? ..Oh and better tunability..You can drive around town qith 19lb's and then have an additional set of lest say 24lbs for the boost..Or vica versa or any combination ya like
Those are good points Damon and since that unit you mentioned will handle 6 injectors that would be the shiznit!:cool: :D
 
Gary,

I looked into adding the same style nitrous system to mine. With the mutiple angles our injectors are positioned, adding length to them isn't an option unless your planning to construct a new fuel rail. Even then several of the injecters are positioned too close to each other and the added length will cause interference on the end that attaches to the rail.

However..anything is possible, it's just a matter of time and money.


Randy,

I've seen some of the turbo guys (GN mainly) add a single large injector into the intake pipe just before the manifold. From what I understand it sprays when a certian boost level is reached. I'm not sure if it pulses rapidly or sprays continously.

At this point I'm happy with the MSD 50s and don't really have any issues with too much fuel at idle or part throttle, but then again I couldn't pass emissions either because of high HCs (unburnt fuel). I think that has more to do with my cam than the fuel injectors, but I could be wrong.

David
 
Damon is right on with my thoughts,The hp will come with the better atomization,
and tunablity.Its a fact that two small injectors can make more horse across the
RPM range, than one large injector.I know this from my cycle racing days.But we
had belt driven fuel pump,and no electronic to control the injector timing.I am lost
with the computor end,of the computor controled injector.

David N.brings up smog testing,With two injectors,and just running one small
injector tuned properly will help pass a smog test.The fuel droplet would be smaller,
so they could atomize at lower velocity in the intake track.Making less hydrocarbons
to show up in the test.With two tunable smaller injectors the mods,cam,ect,may not
be as a big factor as now, with one large injector.In smog testing.

I know that multi injectors helped big time with cycle racing.I just seen that Ford
is now doing the multi injectors with the new blown mod motors.And its been in
the back of my mine since I seen this.I know what it can do for performance.
But I need to learn how to jump over the computor log in front of me.

I wonder if Brian Herron has given this any thought.Or what he would know?
This may be the added feature that would help in tuning a screw blower for
the SC.

Well its just a matter of time and some of the tech info will come out on the GT40
about this set up.But I am ready for the better fuel milage now,and more H.P.
when I stomp on the peddle.

RANDY
 
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Randy,
Nothing wrong with your idea, always good to come up with creative solutions. I guess I wasn't thinking about the driveability with big injectors, although I've seen some EEC-tuner cars that have no problems with those. BTW driveability should also improve if you switched to a low-impedance injector system, because these are more accurate than the high-impedance type. They use a higher current and so they open (and close) with less delay. That delay is what can cause idle and driveability problems with large high-impedance injectors.
 
Randy

Contact me. Low impedance drivers is easy and adding another set of injectors could be done with some work using the EGR valve output to turn on another set or select injectors. The computer would need massive amounts of reprogramming to adapt to wide-band O2 and multi-injector.

Aaron
 
Mike,

Not sure If I am following your electrical logic. If you ran 2 injectors in series there would be more resistance in each injector circuit and current draw would be reduced not increased. The driver transistors only act as an open or closed switch which complete the electrical circuit to ground. They are not the "source" of voltage or current supplied to the circuit.
 
This sounds very interesting how about using alcohol as fuel source in the second set of injectors you could mix and match
 
Motorhead my thought on this subject is to get the SC more efficient.
And then in the final result be able to tune for a screw type blower or
turbos.And pass any emission testing.I don't have a problem with being
tested myself. But somtimes I get involved in projects with others that do worry about this.
I have a couple projects coming up maybe.and tuning is going to be a problem.
I just thought this may be a good angle to look at.Ford has done it for
some reason.And I am sure it wasen't just because they could.

And I am getting ready to start some manifold upgrade ideas,I just thought I
might ad this feature to one of the 4 manifolds that I am getting ready to chop up
and weld back together.Just beatin the bushes to find a little more info about it.

I guess I should have started this on the non-tech side.

RANDY
 
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