additional injectors run by secondary ecu

[chucky]

i'm in the process of building my nt block with turbo pistons, a mild port head, but now my concern is what to do about the fuel setup. i have been reading all posts about it and decided to go with the nt rx7 460 injectors that as some might not know are high impedance, similar to our 240 nt injectors. that makes an easy swap, without the need of a resistor pack. and these inj are easy to find on yards or even ebay, as rx7 owners upgrade their secondary inj very often.
but now there's a problem for most of us that want to do things cheap. what inj to get after those aren't enough? rx7 turbo II has 550cc, but they get hard to find.
so i started thinking about running my old nt ecu for a set of additional injectors. even our 240's could make a nice setup. having stock 450's + 240's could give us 700 cc and at a very low cost. with the advantage of possibly running the secondary set at high boost levels only.
if it works we could even use this setup for a low boost turbo conversion. instead of 450's we could use 240+240. and we all know how cheap our stock nt inj are. mounting the secondary injectors would need some work, we could use the galant 4g64 manifold which i think has the injectors mounted on each runner instead of being in the head as ours.
what is your opinion on this?

 

[green95hrcgs]

A lot of us 2gnt people are running and 8 injector setup. I am in the process of converting to this setup.

Basically we take the lower intake manifold and drill 4 holes, put bosses in them and mount 4 larger injectors and another fuel rail. Connect the 2 fuel rails. We then secure the new fuel rail by making a bracket out of aluminum. Use an 034EIC controller to drive the secondary injectors only when boost is applied.

So the car runs off the stock injectors and gets stock gas mileage and driveability. Only when boost is applied do the secondary injectors kick in with the EIC.

In my car I am running my stock 235cc primary injectors and mounting some 415cc injectors on the secondary rail. That way when boost in applied, I have a total of 650cc to play with. You do need a laptop to tune and it helps to have a datalogger.

I believe the site is 034EIC.com

 

[green95hrcgs]

BTW you will also need a 1:1 fuel pressure regulator.

 

[chucky]

that injector controller 034eic has been out for a while. the audi guys have been using it with success.
i wanted to run a seconday ecu instead of buying any extra controller. dsm ecus are easily available so i think it could be nice to try.
on your inj controller do you need to get signal from MAF ,TPS, knock sensor, or any other sensor?
did you try the galant 4g64 intake mani? you already have the inj located there so there's no need to drill holes on yours.
thanx for the reply.

 

[chucky]

sorry about the mani point. now that i read that you have a 420, it probably doesn't fit.
in my case i could use without much trouble.

 

[Kirby]

I like your idea here as I run the 034eic also with 44lb secondary inj's. The one problem I see in your idea though is using the stock ECU to control the extra injectors. (If the 4g63 ecu is simillar to the 420a) Esp. if it's a N/T ecu. The stock ECU (at least on the 420a) would be problematic as it needs many more imputs than a unit such as the 034. Things like cam sensors, etc, etc. Also if your ecu is an N/T ecu, then it is not programed to fuel above 0psi. Again I will say I know nothing about the 4G63 ECU but these would be my assumptions. It just seems to me it will be very hard to get that system to work. I'm all for you trying it, but I don't see how it could function since you would have no control over how it adds fuel.

 

[chucky]

i have an old school apexi afc (the old old old single knob) that could do the job. (they sell for 50 bucks on ebay)
i think i read something about fuel control with a potentiometer at the vfaq. let me find it again.

 

[Kirby]

i have an old school apexi afc (the old old old single knob) that could do the job. (they sell for 50 bucks on ebay)
i think i read something about fuel control with a potentiometer at the vfaq. let me find it again.

I do not own an AFC but I still doubt it will work. AFAIK the AFC is a piggy back system, which still doesn't change the fact that the stock N/T ECU will not fuel the car under boosted conditions.. May be I do not understand your goal of all this though.. Are you trying to have this device add fuel under boost only or what? I see this making you run extreemly rich during normal operating, (so rich it may not even run) and not do anything for you once the car hits boost. You can adjust with the SAFC as a piggy bacy but 30% more nothing still = nothing you know what I'm saying...

 

[chucky]

you have a good point about the nt ecu. i was not planning to build a staged setup like the one you guys are using that adds fuel under max boost.
my idea was to have both ecus controlling at the same time (parallel setup), independent of boost, and with the afc the additional set of inj could add some extra fuel at high rpm's.

 

[DSM-ZERO]

www.geocities.com/vttalon/
there is everything you need to know about 8 inj. set up
Hope that helps I decided to go with the AEM EMS it is almost done and installed in my car.