So disclaimer etc... i'm not responsible for damage to your car, or your car catching fire etc. Make Sure you can tune your car for the larger injectors (wideband and F-con or AEM F/IC,or what have you), in my case I had to replace the pre-tuned HKS F-con from the turbo kit with the AEM F/IC I obtained a while back to try and optimize what I had at my disposal.

Ok, back to the topic at hand, my friend had some stock g35 fuel injectors left over from his car since he upped the size of his injectors when he installed a supercharger.

So this weekend I went about installing the g35 injectors onto my fit per the instructions I got from the kraftwerks website located here, http://www.kraftwerksusa.com/product...pgrade0209.pdf, so i'm not going to go into tons of detail, and these were pretty much direct replacements.
**Also for this, you would not have to take out the studs or add spacers or anything since the injectors are about the same size as the stock ones, so disregard that about the kraftwerks injector installation

- Disconnect the battery
- remove the intake manifold cover
- Unbolt the black intake portion per the instructions
- using a 12mm wrench or ratchet take off the 5 bolts/nuts holding the plastic(black) intake manifold from the metal one and you end up with this.


- After that, release any pressure from the fuel tank by opening the gas cap

- next put a rag under the fuel line in the engine bay and disconnect the fuel line. First remover the safety cover that covers the fuel line disconnect, the big side faces away from the engine just incase you forget how it goes back in. Then squeeze the turquoise ish colored tabs and pull the black plastic end away from it. in the end the turquoise clip stays on the metal portion of the fuel rail and now it is separated from the fuel line.

- next using a 10mm ratchet, i suggest with at least a 6 in extension, unbolt the 2 nuts holding the main fuel rail down along with the 1 bolt holding down the metal line for the fuel rain.

- before removing the fuel rail, remove the electrical wiring being held to it i the bundle case i guess i'll call it, by releasing the TWO tabs on their underside.

- I also opted to keep my injectors in my engine while I removed the fuel rail so I removed the metal clips holding the injectors to the rail. ** you should use an air compressor to clear the dirt and debris from around the fuel injectors before working on them. you don't want crap falling into the holes where the injectors sat.


Now for a series of pictures to compare the stock G35 injectors and Fit injectors. Note the G35 injector has the blue O-ring at the top and yellow band on it*






ARtys shot


















Note in the Picture below, I sorta filed off the side tabs, I eventually took it off completely so it would fit in the Stock Honda Fit injector plug



















In the Picture below you can see the G35's retaining groove is pretty flush with the fuel rail, while the Fit's is maybe 1 or 2 mm away from the rail.
















Reinstall stuff in the reverse order, I found it pretty easy to put the new injectors on the engine first and then put the fuel rail on them, but that's just me. *don't forget to lube the O-rings up slightly so they can slide into place and to keep them from drying out and cracking etc.* I'm pretty sure bolting down the fuel rail will hold the injectors in place, but I put the metal retaining clips back on anyways, i doubt whether they are holding the injectors in, but better safe than sorry; if they happen to want to slide anywhere, like away from the fuel rail then they'll snap in.


Anyways reinstall everything, close your gas tank if you didn't after just opening it, reconnect the battery (remember your radio code) and CHECK FOR GAS LEAKS


and here's to having slightly bigger injectors for slightly more fun, I wonder what I should do with the extra two injectors...more fuel since the F/IC can control 6 injectors. that might just be more work than I'm ready for.

 

Excellent write up!

Have you had a chance to start tuning your idle and global fuel settings?

And if you can control the other two injectors independently you could spray fuel, water (w/ 0.5-1% soluble oil) or methanol pre- throttle body in the upper intercooler pipe, further allowing you to take advantage of your turbo system.

I was looking at the 8 injector version of the FIC to switch to E85 when I go boosted...

Good job!

 

looks good. just out of curiosity, how many CCs are the the G35 injectors?

 

I wish I could say for sure, but all I know is that it is somewhere around 300ish cc/min injectors. I can't seem to find a good answer on Google. those g35 and 350z guys seem to know, but their numbers seem off. Pretty much 290 CC/min @ 43.5 psi or 3 bar, but at 3.5 bar ~51 psi they say it behaves like 330, but it should be more like 315 ish at least using the calculator provided here RC Fuel Injection

 

When I first started up my car, with these injectors in and the hks F-con my car bogged like mad and had an AFR of like 9 ish i think, I didn't let my car run that long, just enough to warm up the wideband and to check for leaks, which i had none, thank god for that.

When I took out the F-con and put in the F/IC, I had the the AEM program create a base ignition map for boost, and a base fuel map for me using 330 and the new injectors, and 185 as the old injectors and i idle fine right now at ~14.7.

I'm still in the process of fine tuning, but right now i'm trying to get my long term fuel trim and short term fuel trim to zero right now, but I need to keep at it and keep reading up on tuning for everything else.

For some reason I think my kit boost more than it is supposed to so i'm a little worried. The HKS site says their turbo is pre-set to 5.7 psi, but I've seen my boost gauge hit 9, and looking at the AEM program I hit ~24-25 psia max, so 14.7 psia + 9 ish boost, it seems about right.
Because i'm not very well tuned for boost yet with the F/IC, I'm not boosting around all the much cuz i'm not trying to kill my engine, but i do need to get around. I've done 1 fill-up so far and no problems and still 34 mpg, yay driving in vacuum for now.

 

Sounds good. Now to see if I can source an affoedable set to buy.

Thanks for the info!

 

Are you taking Duty Cycles into account with those figures?

Every injector manufacturer I can find, including Injector Dynamics and Fuel Injector Clinic will tell you that you should choose an injector that will meet your max worst case fueling needs at or below 80% IDC, I know I sound like a broken record with this and I am sure you already know this, but it is only out of concern for what looks like a really cool project.

 

Nice! From what you're describing and of what I have read about the FIC it looks like most of the hard work is done!

HKS wastegate actuator probably comes with a 5.7psi spring, but I would imagine that in the small 5 bolt turbine housings, even on a 1.5L we see creep. Or you just need a new boost controller!

Even the GT2554R is still efficient at 9psi, but you are getting close to the far right side of the compressor map at that boost on our engines. You should have enough fuel for 11-12psi safely! That would be a lot of torque BTW. Easily more than double what we put to the wheels in stock trim.

Next mod.... limited slip diff!

 

wew
nice sharing ...

but where can i find G35 injectors ?
i mean from what type of car

 

The Infiniti G35 is what it is sold as in the USDM.. I think it is the Skyline in the JDM. Not the R35, I believe it is sold as the new "Skyline" sedan in Japan.. I will look to clarify this in a moment.

But basically any VQ35 engine you run into should have the right ones. Unless the injectors are different year to year.

 

The RC injectors from Kraft Werks were longer than those and had a wiring harness that adapted them to the Fit due to different connectors. I had to assemble the fuel rail to the injectors and remove some tabs I think.. Anyway the stuff is kind of hanging wedged into place per instructions supplied with the high boost kit.... The guy that first went with the AEM F/IC on his turbo Had larger injectors if I remember correctly..... I guess I need to get the Boom Slang Harness while you guys are still around to explain how to tune with the F/IC.