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A discussion on fuel for the EA82T, to be focused on FUEL RAILS


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Cars of today (atleast performance minded cars) don't have the mass of fuel tubes running around that we do in our EA82T engines.

 

The have fuel rails. Solid pieces of metal (aluminium I'd think mostly) with the centers bored out. To which the injectors attach to.

 

Now, as I've said, to get more fuel from these injectors, we must raise the fuel pressure. After purchasing a second hand SX Performance rising rate fuel pressure regulator I began to investigate how to plumb it into the system.

 

I did think of a way, but honestly, that would just make more of a mess. Mess isn't simple, or necasarly effecient. So, here is my grand thought:

 

Remove all of the manifold mounted fuel lines. Then make up a some fuel rails. See attached for how they could be made. Then, the whole system can be plumbed to the FPR via some nice stainless braided hose.

 

I think it will both clean up the engine bay (appearance wise) and allow for more effecient, higher pressure fuel, to be delivered to our injectors.

 

Your thoughts?

post-98-136027588247_thumb.gif

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we made some for my buddies rally car, just like that you show. the only difference was we used top feed injectors this made it much easier.

 

 

You want to run parallel fuel lines with the feed to the front center to disperse fuel to 1,and 2 then to 3, and 4 with the return to the afpr coming from the t in the rear line. Between 3 and 4.

 

afpr = return from t between 3,4

 

3----t----4

 

Feed to t between 1,3

 

1----t----2

 

This is a mess .................. but do you get it? Take a look at how the og line flows, not so good huh?

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If your going to make a new fuel rail, would be best to just go a step further, and allow the mounting of new injectors, mainly like a standard bosch top feed injector. That way you can go out and pick what ever size you want, there would no longer be the limitation of stock ones. And it really wouldn't take much more fabrication. I have thought long and hard on this for the EA81T (same fuel rail problem). Mine was mainly because of the integrated FPR, if that thing goes out (20 yo car, bound to happen soon) I would be SOL. As for the RRFPR that I mounted on mine, I just plumbed it into the return line, the stock FPR works, but as the boost goes up, the RRFPR increases the fuel pressure in the upper regions.

 

Your RRFPR has 3 lines? :confused: Mine only has 2 fuel lines, and the one vacume attachment, it goes into the return line, as the boost goes up, the FPR closes off the return more and more, increasing the pressure.

 

But I hear ya on the mess of lines everywhere.

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Thanks for the link. I've already looked at that and tried to see if it was applicable to our injectors. It is not. Our injectors are an older style that use a needle valve to dispense the fuel. Any modification of the tip would mean serious reworking of the valve.

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You are correct they are top feed. I never looked that close I just thought they were side feed like the EJ22t. Your last drawing was basically like the one I was trying to show. I just used a t in the line. to the fpr then on the other side port used a fuel pressure gauge.

 

Josh

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Hey hey....another thread just for me..err, all of us EA82T guys.

 

Ya know, i think there is an aftermarket fuel rail system for the EJxx engines...I think....with the right backyard equipment, we could have a home made type system, for next to nothing...other than the cost of some quality parts, such as fuel injectors and a regulator.

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Originally posted by Subarutex

Yes, thats very much what I had in mind.

 

Although, i imagined only one steel braided hose going to each fuel rail. Then they'd Tee right before hitting the regulator. Such as in the first of my little drawings.

 

I think you need to take a good look at the stock set up, your "performance" set up has to nearly model this. The fuel comes from the pump, then goes through filter, then the "rails", then to the regulator. This (regulator)is the restriction in the system that causes the pressure to raise or lower, then excess fuel returns to the tank.

 

Tex or any one that is confused give me a call if you want to chat

 

253.230.3040

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Megasquirt is on my list of wants... However, the whole assemble it yourself thing has me a bit shy. I've also been looking a lot at SDSefi fuel control systems. Seem pretty good for the price (under a grand)

 

Nice find on that fuel rail stock! You win!

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That's funny as I am in the same boat! I like the MS because it is so adaptable, and the following it has by some VERY smart guys is phenominal.

 

It is VERY DIY, but I think with the enough patience I could do a decent system for far less than SDS and have money left over!

 

I've been on the MS list for a few months now, and the potential of MS is insane, and the new system coming out - UMS will absolutely rock.

 

I'm personally waiting for UMS, and if it works well on there, I will build a system for my subie. UMS is a full stand alone - (MS has versions that do spark as well though).

 

Solves the problem of using better injectors with custom fuel rails and having a kick rump roast computer to run it all. The EA82T would really shine if it had decent modern fuel control - we might actually have a car with decent gas mileage AND power!!

 

Sorry if this off topic from the post...

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My thoughts would be that it *may* be possible if you were able to set up a wide band O2 sensor that the ECU would use in a closed loop system - IE using feed back from the wide band to determine fuel requirements. (Perfect for highway cruising only)

 

R&D would definitely have to go in if you wanted peak power AND efficiency. Which is what I want :)

 

R&D is basically a necessity if you want it all - but I personally would enjoy the tweaking and tuning needed to get it right - beauty part of MS is, once more people do it, these maps can be used as baselines for others.

 

If it takes off, then very little R&D would be needed since there would be such a large base of knowledge to pull from.

 

This relates to the post since fuel management would be manditory almost since the new fuel rail opens up the possibilities of injectors into the equation - most of which the ECU can't handle.

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I personally like the MS and EDIS idea if UMS doesn't take off - crank fired trigger ignition - very cool stuff...

 

Sky is the Limit with MS - Boost control, water injection, extra injectors etc etc.

 

I am definitely interested in this for my EA82T because if it was actually economical to run - I'd NEVER get rid of it. (Even is costs up to $1000 CDN)

 

Again sorry if this is jacking the post ...

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If you will build me an MS... I will put it on my car. PM me.

 

Now, i'm going to buy 2ft (the minimum order) of the fuel rail stock. By my math, that should be enough to do 2 engines. (2 rails per engine at 6" a piece).

 

Before doing this I'm going to ask them how much it would cost for them to drill and tap the injector ports, and tap the ends to accept fittings. But this is all stuff that with a decent drill press and some time can be done by me.

 

I'll go ahead and make both sets. After i get it running, i'll sell the other off, or use it as a guide that we can make more of them.

 

So there is my $20 and a lot of time into this project... I'll let you know how it goes.

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Got an email back from Ross's Machie shop. He didn't really give me a quote for them to make them. Was honest with me, and said I could do it, same quality, and do it cheaper.

 

That said, i went ahead and order 2 feet of the Dash 6 extrusion. I'm thinking now, that each rail will only need to be about 4" in length. So, i'll be able to yeild 3 sets off this order.

 

The guy was nice enough to tell me what drill to use, and what tap to use. Once I get the extrusion in, and get paid... I might pick those things up. Unfortunately, i still have a life to lead... and money is in scarce supply.

 

If I could sell a fuel rail kit for say... $50 would there be any interest?

 

Kit would include fuel rails and fittings. Either NPT to Barbs (for rubber lines, or NPT to AN fittings (for steel braided hose).

 

Hell, depending on cost I may be able to include the hose needed. Then all you would need is the pressure regulator.

 

Cheers!

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Ideally, finding injectors that the stock ECU could drive with more headroom than stock would be ideal for someone just wanting an upgrade.

 

That would be cool since you could do the upgrade in steps so the total outlay in cash and downtime would be at a minimum.

 

Being married with more than one car project means that I have to VERY choosy on how I spend money...

 

To be honest - I would rather build my own set of rails, a bit because the cost savings, but mostly - the satisfaction of building it ALL myself.

 

The great opportunity here is to develop an upgrade that everyone could duplicate for a minimum of costs. For those that need parts pre-built - great! Nice opportunity to make a little money helping another enthusiast out.

 

Key to this upgrade is getting the upgrade sorted out so that it is a bolt in upgrade that takes x amount of hours with x parts from the wrecker / auto parts store.

 

Anybody know the specs on our injectors? Anybody ever get them cleaned and flowed? I may have had the info at one time as I had a set cleaned and flowed - but I no longer have the info :(

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Use stock injectors for now. Yes, hook them up via a barb to the fuel hose. There are a wide variety of injectors we should be able to use in the future... when we find the limit of the stock injectors.

 

Basically, the reason I offered to make the rails is to save everyone the hassle of having to get more rail than they need. I'm into just the 2ft of rail extrusion close to $40. Half of that, I won't use!

 

$50 was just a bench mark, i gather they'll be much less. I'm not looking to make money at all. I am however looking to cover the costs of what needs to be invested.

 

$40 for rails

$20 for the tap? Haven't found one yet... NPT ones are hard to find I guess

$10 for the fittings per car?

 

I guess maybe i'll just sit on the stuff and let others invest and equal amount of money, and end up with things they won't use again. (how many times are you going to need to use an NPT tap???)

 

To each his own. Follow the link above to buy your extrusions. I'm using Dash 6, other size is a little over the top for us I think.

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If the EA82T was the only I car I wanted to do this for - I'd be all over your offer. (Didn't meant any other way...)

 

Unfortunately (fortunately?) I have two other cars that I want to build custom fuel rails for - both inline 4's. (One turbo 2.2L and a NA 2.0 L) Being part of a car club, I could always build a couple for other guys as well. I can see this having a bunch of uses - especially guys wanting to do a CIS conversion to regular EFI.

 

That said - in my personal case it, I can make use of the items needed to machine my own bosses. (I like collecting tools too!)

 

I was kind of thinking of the dash 10 for my turbo car, and the Dash 6's for the other two applications - but I have no idea! Dash 6 would probably do all cars without any problems at all...

 

 

Rabin

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