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The Truth about RX Turbo Fuel Injector Flow Rates

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Hello all,

 

I just got my fuel injectors back for my RX Turbo. For those that don't know, I own a 1988 1.8ltr Subaru RX Turbo (See sig). I sent my fuel injectors to RC Engineering Tuesday via Fedex overnight to have them cleaned. I had them overnighted back to me (I hate waiting) and just picked them up. I need to keep this brief but I'll be back with pics later after picking my wife and kid up.

 

The truth is, the RX injectors do not flow 180cc, 185cc or 190cc like what was previously believed or told. The RX turbo injectors flow an average of 245cc/min. I have two that flowed 246.0cc, one 243.0cc and one 244.0cc after cleaning. I'll post up my before and after cleaning flow sheet as well as before and after cleaning pics. Right now, I need to drive up to the dealership to drop them off to be installed.

 

BTW: The RC Sheet shows.......

Injector Type: P&H 2.5

Injector make: JECS

RC# PJ2H-245

Part# A46-000970 8217B

 

If this is misinformation, I apologize. These injectors could very well be aftermarket fuel injectors if the stock RX turbo does come from the factory with 185cc fuel injectors. I do not know. This is what I got though.

 

RC Engineering do not carry any injector upgrade for JECS made injectors for Subaru. I just called them before typing my last sentence.

 

So there you have it. Proof will be shown in the pics I post up later. Comments, suggestions, flames are welcome. :) I'm just excited that I finally know what the truth is. I hate not knowing. Laters!

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I'm excited! I've been looking into putting bigger injectors in the motor I'm building for the RX.. I mean, someone else's project:D Nice info, just keep it coming!

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245cc at what pressure? The 185ish figure is at the stock pressure of 36psi, alot of systems run 45psi. A 185cc @ 36psi injector would be about 231cc @ 45psi.

 

Just to be sure we are compairing apples to apples.

Gary

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I'm confused about one thing, RXs use the same injectors as all the other ea82t cars right?

 

Thats what I thought, now I'm not so sure. Makes me wonder about my injectors though because EA82 injectors can be interchanged with EA81Ts. Guess I'll have to send some injectors to RC.

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245cc at what pressure? The 185ish figure is at the stock pressure of 36psi, alot of systems run 45psi. A 185cc @ 36psi injector would be about 231cc @ 45psi.

 

Just to be sure we are compairing apples to apples.

Gary

 

Well dang! I never even thought about this. I'm not sure if it was even mentioned in some of the past posts. :banghead: In this case, we DO have 185cc fuel injectors because the test pressure on my data sheet is 43psi. Now I look like a fool. :o I'm a disgrace to the board and I'll never return again. Just kidding!

 

I'll go about posting up the sheet in a bit. I need to scan it.

 

On another note: There is a standard pressure that injectors are tested at despite what they may flow at a higher or lower fuel pressure. What is this standard?

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I'm confused about one thing, RXs use the same injectors as all the other ea82t cars right?

 

 

I hope they do - my ea81t has three es81t injectors and one ea82t injector that i believe came from an rx.

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Here's the data sheet. Enjoy!

 

mini-rxfuel-injector.jpg

 

BTW: Here's something I thought that was interesting. I had the fuel injectors numbers from 1-4. They were numbered according the the cylinder they were spraying into. Cylinders #1 and #3 (which are closest to the turbo, especially #3) faired worse than fuel injectors #2 and #4. Even after cleaning they both were worse than the driver's side fuel injectors. They two good and two 'bad' fuel injectors were pretty much consistant with each other whether they were bad or good. What do you think about this?

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On another note: There is a standard pressure that injectors are tested it despite what they may flow at a higher or lower fuel pressure. What is this standard?

 

I think its 42 or 43 psi, something like that.

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Did you have the dealer remove and install the injectors? Im wondering how hard it would be to get something like this done. Not sure if I'd be able to take down the RX to have it done though :|

 

-Brian

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Did you have the dealer remove and install the injectors? Im wondering how hard it would be to get something like this done. Not sure if I'd be able to take down the RX to have it done though :|

 

-Brian

 

Yes I did! Was going to do it myself but felt impending doom. Rather let someone else deal with it. Two parts broke off due to rust and being old, where the screws held in two injectors...or something like that. The dealership fixed it at their expense. I like that! :)

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BTW: Here's something I thought that was interesting. I had the fuel injectors numbers from 1-4. They were numbered according the the cylinder they were spraying into. Cylinders #1 and #3 (which are closest to the turbo, especially #3) faired worse than fuel injectors #2 and #4. Even after cleaning they both were worse than the driver's side fuel injectors. They two good and two 'bad' fuel injectors were pretty much consistant with each other whether they were bad or good. What do you think about this?

I think you're onto something there. Extra stress as a result of the heat?

I just had #3 injector stop functioning when HG 1-3 blew. I think the injector was on it's way out for a while causing that cylinder to run leaner it was most likely the first to ping and suffer from any hard driving.

It'd be interesting to see what others have found as far as flow rates go 2-4 compared to 1-3 maybe this is the source of 1-3, 3 the worst, running hot eating ring landings/pistons and HG's.

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I recently had a set done, mine tested around 240. I only had 1 dripping, you had three, your car must of run like shiat. It seemed to help my car a lot but i did some other stuff at the same time so it's hard for me to gauge the improvement BUT I'm convinced it was worthwhile and have urged others to d it as well...money well spent. It took about an hour to carefuly swap the cleaned ones in.

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Say, do EA82s have only one injector? Or do they have 4, like the EA82Ts? I wonder if having mine cleared out would do any good.

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Say, do EA82s have only one injector? Or do they have 4, like the EA82Ts? I wonder if having mine cleared out would do any good.

SPFI cars, like yours (it's a Loyale) have only one injector in the throttle body.

MPFI cars (1985 GL-10, XT's, and all turbo cars) have one injector per cylinder. They also have a special intake manifold and heads that differ from carb/SPFI cars.

 

MPFI N/A is a better than SPFI for performace consiterations (better air flow - and about 7 more HP for late model MPFI N/A (on XT-4) vs Loyale SPFI), but SPFI is probably better for reliability, as it is a simpler system - parts are also MUCH easier to find for SPFI cars.

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$115 including shipping.

My car wouldn't idle right and was running very rich.

I also did a basic tune up including O2 sensor and PVC (OEM) valve.

The car runs and idles perfect now and absolutely no hesitation or surging.

I did also remove and sand all the grounding points :-/ -later, I'm going to add some additional grounding wires.

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I guess that also answers the question that higher fuel pressure will increase fuel flow to the cylinders. Which some of us know that...:rolleyes:

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245cc at what pressure? The 185ish figure is at the stock pressure of 36psi, alot of systems run 45psi. A 185cc @ 36psi injector would be about 231cc @ 45psi.

 

Just to be sure we are compairing apples to apples.

Gary

 

I had to REALLY think about this for a bit. Are we all really sure that RX Turbo fuel injectors are 185cc? I found my old post at XT6.net where I posted the results of having my XT6 fuel injectors cleaned at RC Engineering. At 43psi of fuel pressure, it came out to 185cc. Since the XT6 is basically a 6 cylinder EA82, would you think that this is what was put into an N/A EA82 engine? If so, would this really make our RX turbo fuel injectors 245cc units? (I have my own thoughts on this but I just wanted to see what people think about all of this). Here is the result of my XT6 fuel injectors that got cleaned at RC Engineering at the same fuel pressure as my RX Turbo fuel injectors.

mini-xt6fuel4.jpg

 

Note also that the XT6s fuel injector make and type is different than that of the RX turbo fuel injectors. Another question would be what is the make and type of fuel injector of an N/A EA82 engine? Is it Nippon Denso saturated (XT6) or JECS Peak & Hold (RX Turbo) fuel injectors?

 

Just trying to make for some good discussion.

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The ones I sent in were random injectors from a couple different, non RX, turbo intakes, I found 4 that matched and looked good. I think all the turbo injectors are the same, N/A may be different?

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kevin,

 

good to see you are still in the game...and still being innovative.

 

good luck with this thing man.

 

Wow! Dennis, haven't heard/read from you in what seem like ages. Glad to see you are still around.

 

Whatever happened to that RX turbo that I foolishly didn't purchase from you?

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im still around, just focusing on other things...

 

about the rx:

 

its changed hands a few times.

 

i think i saw it for sale in the marketplace last week.

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