# GA16i injector



## SuperSentra4203 (Dec 17, 2002)

Plans are coming together fine for my turbo GA16i, but one area has me wondering. The injector. I'm not sure it it can possibly flow enough to provide 200+bhp. I can easily get an aftermarket fuel pump and lines relatively cheap (good ol Summit) but the injector has me wondering if it can be done. There is a strong will in me for this project, and will be done. Regardless of how rusted my car is. I'm thinking a VG30i injector can be used, but I cannot get a look at one. Are there aftermarket universal injectors that I can use. I could always do a MPFI conversion, but TBI is a requirement for me. Can anyone help me of give me advice? Any would be appreciated, as well as opintios on this project. I want to know what y'all think


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## minute rice sentra (Mar 21, 2003)

what car has that engine? My bro has an '85 300z with a VG30DE(I think) and it has port fuel injection which doesn't seem very compatible with any tbi configuration.


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## fastpakr (Sep 18, 2002)

minute rice, the E in DE means port fuel injection. an I motor is throttle body injected.


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## minute rice sentra (Mar 21, 2003)

I know that, i was just wondering what car has the VG30i.


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## SuperSentra4203 (Dec 17, 2002)

I'm pretty sure it is one of the old Pathfinders.


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## minute rice sentra (Mar 21, 2003)

a guy at my work has an '87 pathfinder and i remember that it is tbi so i'll look at it tomorrow.


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## Crazy-Mart (Jul 14, 2002)

i was told today there were upgrade to those injector but i havent looked at one yet...


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## SuperSentra4203 (Dec 17, 2002)

Eh, just looks ike i'm gonna retrofit a high flow MPFI injector from some car to my throttle body. I'll check out the Pathfinder injector though.


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## fastpakr (Sep 18, 2002)

I'm really not sure how this will affect you, but an MPFI injector is almost always high resistance, where most TB injectors are low resistance. Something to check into before you switch the two. Also, what fuel pressure does the Nissan TBI run at?


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## minute rice sentra (Mar 21, 2003)

fastpakr said:


> *I'm really not sure how this will affect you, but an MPFI injector is almost always high resistance, where most TB injectors are low resistance. Something to check into before you switch the two. Also, what fuel pressure does the Nissan TBI run at? *


He could play around with some resistors to get the resistance down to the right value and my haynes says 34psi @ idle for the ga16i


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## SuperSentra4203 (Dec 17, 2002)

34psi at idle is the fuel pump output. I think the injector only sees about 10-14psi, the rest just goes back to the tank via the return line.


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## Galimba1 (Aug 16, 2002)

Crazy-Mart said:


> *i was told today there were upgrade to those injector but i havent looked at one yet... *


Who told you? I'm looking for a bigger injector to replace stock on my ga16i. I was going to look into modifying a hi flow ga16de injector, but I'm not sure yet. Definitely a throttle body fuel injector would be a hell of a lot less troouble than a modified mpfi injector. If you got more info on upgraded tbi injectors, I'd like to hear it.


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## SuperSentra4203 (Dec 17, 2002)

Check this out, www.rceng.com 

They sell high-flow injectors, and can upgrade just about any injector up-to a 100% increase in flow for $175


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## Crazy-Mart (Jul 14, 2002)

I did some search and coulnt found any.. but i could have searched more ...


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## Galimba1 (Aug 16, 2002)

SuperSentra4203 said:


> *Check this out, www.rceng.com
> 
> They sell high-flow injectors, and can upgrade just about any injector up-to a 100% increase in flow for $175 *


well, I inquired at RC Engineering a few weeks back, and wanted to post this, but the board was down for a bit. This was their reply:

_Hello Kevin,

Unfortunately, we cannot modify a TBI injector to flow more. We suggest increasing the fuel pressure or adding additional injectors.

Thank you for your interest in RC Engineering. Please feel free to call or e-mail us with any further questions you may have. 
_

So, now my question goes to SuperSentra: besides puting in a higher pressure fuel pump/regulator, how do you get more fuel into the tbi? I'm still not certain if a mpfi injector can be modified to work in a tbi.


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## SuperSentra4203 (Dec 17, 2002)

I plan on using the GA16DE's intake system if I can. Plain and simple, add more injectors like they said. I've seen this done on a few cars. The main problem is how the TBI injector actually gets it's fuel. It's not like a MPFI injector at all. It's not top-fed, but side'-fed. All around the injector in the center is like a small metal screen, where it will get the fuel. The injector is 'sealed' in a round cavity where the fuel is fed into. I wish I had a digital camera so I could post pics. I tore the throttle body completely down at 3am in the morning last night (too much coffee)

Here is another possibility, run two throttle bodies. Either way I look at my project, i'm gonna be doing some custom fabrication. By theory, an intake manifold can be custom made with metal tubing. Several problems will arise and must be addresses. Coolant jackets (I figured that out) and vacuum lines (flanges must be welder near what the OE flanges are)

Unforutanly, the GA16i's throttlebody is really small. Not very performance friendly. My buddy was actually thinking of ditching the computer system and fabricating a Holley Carb to it. That idea has become appealing to me.......

As for the MPFI injector, I'm just gonna ditch that idea unless it's my last resort. By the looks of it, the OE FPR can be tossed for an aftermarket in-line unit and a aftermatket fuel pump (i.e. Walbro 255) Also, by-passing and tossing the Active Carbon Charcoal Canister looks like it has performance value. A lot of people do this, especially on DSM's. I need to get some spec sheets on all of Nissan's TBI injectors to see which one flows more. Also, I was looking at my sisters 90 Cutlass with the Tech-4 TBI in it. The injector looks like it might work. It should flow much more considering it's supplying fuel for 2.5L.


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## Gsolo (Sep 11, 2003)

holley would be cool  i was gonna say though look into the chevy 350tbi but that would be way to big so yeah the cutlass but then how do you wire it up so that the nissan ecu would work right with it


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## SuperSentra4203 (Dec 17, 2002)

The injectors are two wire, positive and negative. Simple. If the resistance is incorrect, I can simple wire up system of resistors to bring it to the OE resistance so the ECM doesn't freak out. I was looking, and Holley sells TBI units. I'm gonna look more into it. I doubt the 350TBI would be too big, as i'm gonna turbo this sucker. At the most, it just won't be at it's full potential. I also inquired on a injector that flows 100% or more over stock. I should get an e-mail sometime in the near future. Meanwhile, i'm gonna fiddle around with the GA16i's intake system to see what can be done.


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## Gsolo (Sep 11, 2003)

or if you want to keep computer control with a carb( dont know why you would)look into the Oldsmobile 307. You'll find it easily in like 1988 full size oldsmobile and cadillac fleetwood brougham d'elegance (but its considered just a brougham...fleetwoods suppose to have 4.1 and 4.5). now the olds 307 was very weak in power, [email protected] and [email protected] it had a Quadrajet 4barrell computer controlled....just a dumb though but if you could get that to work then you would flow alot of air and fuel and could still be economical when just driving with the primaries then floor it and open the secondaries i know they put this carb on others but not sure what so just used the 307 as example. And yeah this is far off and i'll probably get flamed for mentioning a domestic carb for a nissan  


ohh, and if you did use a carb you have to box it for the turbo...you probably knew that but if you dont its cause a carb isn't air tight sealed so you have to make a box to go around it...or you put the turbo setup to suck air through the carb but its a little funky to do that there are pros and cons with both....and after all this writing i did i'm gonna say screw it and stick with finding a tbi  ....good luck with your project, you need it


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## SuperSentra4203 (Dec 17, 2002)

Aghhh.... I might as well run the GA16DE's MPFI. Question is, can it be done on a SOHC head???


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## Gsolo (Sep 11, 2003)

...so put the DOHC head on it ...but then that probably ruins the purpose of what you're going for doesn't it  i dont see why you couldn't put the mpfi on it, you'd have to do some custom work though


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