Safe to downgrade from 440 injectors to stock EJ22T injctrs?

[impreza_GC8]

I have side feed gray 440cc injectors on my turbo'ed Legacy but one of them just went out yesterday. I'm currently running 11psi with an MBC on a stock EJ22T fuel pump with a VF8 turbo. I got horrendous gas mileage with those injectors. I was wondering if I could get some stock EJ22T injectors and still run 11psi on my VF8 safely. I do have a Walbro 255 fuel pump in a box that I could install if needed. So, is 11psi safe for EJ22T injectors?

[Imprezive]

Well first off, unless your factory fuel pump is crapping out and making your car run lower than spec fuel pressure the Walbro pump wont make a difference. But thats not to say that you shouldnt just put it in anyways and have the piece of mind.

When I first rebuilt my engine w/ delta stg1 cams and ported SOHC heads I was running a JDM TD05-16G w/ stock injectors. I ran it around gently to get the engine broken in and then installed my Apexi SAFC and AVCR and took it to the dyno. Before tuning I did a base pull and with factory ECU controlling the fueling it was running a bit lean @ 12psi max. Not catastrophically lean, but nonetheless more lean than we wanted.

Once we got it tuned we were adding up to around 12% fueling at low throttle (below 30%) and probably around 10% at high throttle (above 30%). This got us close to an AFR of around 12.1 I believe. Its been a long time tho so don't hold me on this...

The VF8 flows less than a 16g for sure tho, so you'd probably be just fine at 11psi.

[impreza_GC8]

^ This is helpful! Yes it is safe to say a VF8 flows less than a 16G! Any more input on this matter? For the record, my setup uses 2.5L block halves so I'm not sure if the larger displacement would have any affect on fueling when using the smaller injectors. I read somewhere on here that a member *thought* the stock fueling system was good to 16psi. Can anyone verify this?

[gijonas]

Sould be ok to about 13 or so anyways.leave the rest for safety.BTW i got some stock injectors for sale if needed.

[Imprezive]

Another quick note: back when I was tuning my car we were experimenting with letting it spike to 14ish psi and then drop down to 11 before the ecu cuts fuel and the stock injectors never let it lean out. This is with the same setup that I mentioned earlier.

Your 2.5L block will pull more air in with each stroke than a 2.2, requiring more fuel, but with your setup I still think you will be ok. If there is a dyno near you it wouldn't hurt to do a few pulls just to make sure. I'd also reccomend some kind of fuel control if you wanna boost more.

[impreza_GC8]

Thanks for the help guys. I just realized though that I'm using an EJ20G intake manifold. I assume that the car also has EJ20G fuel rails so that means I am limited to injectors that would work on an EJ20G which rules out EJ22T injectors completely. I guess its better I figured it out before I bought any and pulled the current injectors out.

[Imprezive]

Well the ej22t injectors are side feed, I believe the 20g injectors are to right?

[Legacy777]

What are you doing for engine management?

[ScottyS]

The ej20G injectors fit the 22T fuel rails, it might also work the other way around.

I ran the VF-8 at 12psi with the 22T ECU and injectors for a while - it was OK, but did not have the response that the Revtronix Stage 2 setup does. Do I think that 11psi is safe? Yes.

[Imprezive]

What are you doing for engine management?

It would appear he isn't using any beside the mentally challenged OEM ECU...