Notes from a 440cc injector install

[BSOD2600]

I purchased my 440cc injectors straight from Japan via the ebay user theglobesavinggroup, which a few other users have used too. Next, I followed n2x4's 440cc guide and purchased the 2 remaining o-rings.

Diagram:


I started out and removed the left fuel rail. Wow, those fuel rails are a major PITA! Save yourself the hassle and don't remove them! My injector seals (under the fuel rail) were still nice and soft. To remove the injectors, sprayed some WD-40 on the top lip. Let it soak for a few minutes. Next, take pliers and turn the injector side to side some, so move around the WD-40 for lubrication. Then as you continue to turn back and forth, pull up and it should pop out.

Side by side of the stock and 440cc injector:


It appears the fuel injector seal rings have changed over time. Hard to see in the pic, but the stock has a lip/ridge inside while the new one does not.


It changes how it sits on the bottom of the rail. Once again, hard to see.

Old


New


After getting the left rail installed, it seems the gap between the rail and engine is abnormally large. Something to worry about?



Anyways, got everything back together and took it for a 5 min drive. While I understand the ECU is still learning, it's got a lot to catch up! Cruising on the streets it fluctuates from 12-16 AFT. At 3/4 WOT the AFR drops down to ~9.5 -- very rich. When idling for a bit, it gets super lean; around 28-32 AFR. Isn't that too lean and can damage things? I'll be taking it for a 150mi drive this weekend. Hopefully after that, the ECU will have adapted.

[Legacy777]

The ridge on the old seals is just due to age.

What are you measuring your AFR's with? I'm assuming a WB?


This is just a general comment for people looking at doing this. I know people have done it, but you can't expect to stick larger injectors in a car and have the factory ECU run them perfectly. It's far from a desirable setup. It may run....but it's not going to run the way it should run, despite how much "learning" the ECU can do.

[ScottyS]

Notes are good.

The other day I pulled the stock injectors from my spare manifold and also pulled the 440's out of the EJ20G I have sitting around.

The seal rings on the 22T rails were starting to crack on the inside of the base, whereas the seal rings on the 20G rails look fine.

Once the 440's get back from WitchHunter, I will pre-assemble the injectors and rails, and then pull the rails from the car and drop in the assemblies. I will be using new o-rings on the rails as well.

I plan on dropping the JECS, Revtronix chip, and TD04 on at the same time, so I won't find out how the car runs with the stock ECU and new injectors.

[BSOD2600]

What are you measuring your AFR's with? I'm assuming a WB?

Yes, LC-1. The 2nd drive later in the day, wasn't nearly as bad though, so it appears to be learning fast. Taking it for a 150mi drive tonight.

I plan on dropping the JECS, Revtronix chip, and TD04 on at the same time, so I won't find out how the car runs with the stock ECU and new injectors.

The JECS and Revtronix are sitting on my shelf. Next week, my plan is to datalog the change in things with just the 440's. Then drop in the MAF/chip and datalog again after some driving.

[n2x4]

Good post! It's funny you put this together because I was working on compiling my findings too.

Believe it or not, I've only managed to put 60 miles on my car since introducing 440's to it. It runs like poo. I"ve got a wideband, but haven't hooked it up yet.

I can quite easily tell that it runs very rich under full throttle and bogs (to be expected). It's much faster under part throttle. Easily fixed, but it's kind of fun to see if the ECU can ever figure out what's going on on it's own. Susiemk and I were discussing all the options to help the ECU with the larger injectors.

You've got
1. Revtronix Chip
2. Some sort of piggyback (Apexi AFC anyone?)
3. Lowering base fuel pressure with a FMU

As far as the rails seating, I don't remember if there was a gap when I did mine or not. I'll try and check this weekend. I just remember that I forgot to install the spacers between the rail and manifold and ended up bending my fuel rail. I managed to get it straight again but I was pretty worried about that and probably didn't notice any gapping issues.

[asc_up]

The ECU will eventually figure out how to run them properly, at least mine did. Also, my injectors definitely didn't have that gap between them and the rail. Did you remember to put back the little risers that the two bolts that hold the rails in place go through?

[BSOD2600]

Did you remember to put back the little risers that the two bolts that hold the rails in place go through?

Well... on the left rail, I only found 1 of the spacers when reinstalling it :-S. So that's possibly a cause of the gap. Should probably fashion something for that gap. Another thing is that I didn't pay close attention to where the bracket for the coolant overflow tube goes -- under or over the fuel rail bolt holes.

Well its been ~150mi since I installed the injectors. Cruising down the street, they're alright. The AFR stays around 14.6, but the ECU does 'hunt' for it more; i.e. it bounces around from 13.5 to 16 AFR a lot more often. WOT (in 5th gear) it's adapted to around 10 AFR. Idle is still unhappy. There must be 2 different idle modes the ECU uses. Sometimes after city driving, I'll pull up to a light and it will idle around 700 rpm, ~16-18 AFR, and runs ok. Then after ~10-20 seconds, the idle drops to ~500rpm, AFR leans out to ~26, engine vacuum changes from ~20inHg to ~15 inHg and it 'hunts' for it (goes up/down ~2inHg). Maybe the IAC is opening/closing during this time which cause the vacuum change, idle to go really rough, etc?

Hopefully later this week I'll datalog the changes.

[asc_up]

The problems you're describing are the exact same ones that I had when I forgot to re-install those spacers. It must have caused a leak without them. Find them/fabricate some and install them! I'd be willing to bet money that's the problem.

[Airgne]

ok so i found some "grey" 440cc injectors(dont know what from), but i also gound "yellow" 440cc injectors(these say from phase I wrx). how can i tell with out buying them and shipping them out for diff between the grey and yellow?

dont mean to high jack thread. better than starting new one. also i searched.

[BSOD2600]

The problems you're describing are the exact same ones that I had when I forgot to re-install those spacers. It must have caused a leak without them.

The idling problems are a LOT worse with the stage 2 chip in. Finally stuck my head near that large gapped injector when the idling was bouncing. Sure enough, on each rpm drop, I can hear a sucking sound coming from that area. Damnit! Now to find/fabricate up a damn spacer...

[ScottyS]

Ouch, if you can actually hear the air going in, then I'm sure that's really bad in a lot of ways.

Are you talking about the washers between the intake manifold and the rail that the mounting bolts go through? Those should be pretty easy to get ahold of. I noticed that the spacers on my EJ20G are identical, so they are probably on a lot of models.

[asc_up]

Yup, those are the ones he's talking about. The EJ20G that I got my injectors from had the spacers, too; good point Scotty.

I bet they aren't very expensive at the dealer either.

[BSOD2600]

I bet they aren't very expensive at the dealer either.

No dealer in Seattle has them in stock.

Ordered from subaruparts.com last week, but my order is held up for another unrelated part (36037AA140 - ASSIST SPRING B) when is on 'vendor backorder'. Contemplating putting in some large washers until I get the right spacing...

[asc_up]

Hmmm, want me to check the Tacoma dealer for you? I'm not sure if they're open tomorrow, but I can try. If they're cheap, I can just buy them and then mail them up to you.

[BSOD2600]

Subaruparts.com is Bruce Titus Subaru (in Tacoma). They too didn't have it. Thanks though.

Anyways, went out today and ghetto fixed it till my part arrives. Moved that coolant bracket to the TOP side of the rail. Also inserted two thick washers in place of the missing spacer -- exact height fit! That closed up the gap some between the rail and engine. Now it idles a LOT better.

[Legacy777]

Go to a junkyard and get them off a 90-91 legacy.

[wtdash]

Yes, this is an OLD thread but I have 2 issues both related to this install. I've put 440's into the stock '93 EJ22T rails playing w/my EJ20G Z4 ECU install.

1. My '93 EJ22T fuel rails do NOT look right w/the the spacers installed...they look like the pic above where the bottom of the rail is sticking up. With OUT the spacers they look about right, but I had a leak where the rail fits in the 'fuel injector seal' from the 1st pic, but only on one side so I tried them anyway and they stuck out too much, IMHO.

Anyone know if there was change in either the intake manifold (IM) or the rails on the later SS/TW's?

2. The 'fuel injector seal' P/N: 16608AA020, has a bigger chamfer one side than the other - Which side goes down in the IM? I managed to NOT notice this when I pulled them out to replace w/the new seals.

Thanks,
Td

[Legacy777]

The intake manifold did change in the 93 MY for the turbo engines. Don't know the specific changes. Also the number of spacers and their setup did change as well.

As for the injector seal, it shouldn't matter. I usually put the bigger chamfer up.

[cj91legss]

Just out of curiousity, how common is injector failure with 440s? I have replaced 2 within the last 6 months

[BSOD2600]

Just out of curiousity, how common is injector failure with 440s? I have replaced 2 within the last 6 months

I had 1 go bad on me after ~15K miles and replaced it. No active CEL either, just an occasional stored CEL (found via RevScan). Only found it was bad after testing its resistance.

[cj91legss]

both times i had one fail, it threw a code. Guess it was made simple for me.