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subarujim01

adding fuel injection to Ea71 1978 Brat

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I am considering adding a fuel injection system to my 1978 brat with a EA71 engine.

Holley has a new 2bbl EFI kit available "Holley Sniper EFI 2300 self-tuning master kit",

with a adapter plate that will fit unto the Weber plate I added when I upgraded to that from the orginal carburetor.

Has any one tried this already?

If so what issues did you run into.

I have added a AC system the Brat but when I tried to use it last summer here in Tucson

the current draw on the engine is too much , unless I change the electric chock to a manual unit on the weber carb.

 

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My guess is that that system won't be able to turn the wick down far enough to not be constantly over-fueling that little 1.6L engine, even at full chat.

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7 hours ago, carfreak85 said:

My guess is that that system won't be able to turn the wick down far enough to not be constantly over-fueling that little 1.6L engine, even at full chat.

Actually its been surprising what the new EFI (throttle body) kits can do. However you do have a point and should email them to find out if it can handle it.

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Just looked up the kit on Holley.com.  It's rated at 350 N/A hp, but in the Q&A section they say they have tested it down to ~100 hp.  That's still a solid 30+ hp more than even the healthiest EA71 ever made, so it would probably work, but you'd be running pig rich all the time.

I would pass on it, but it is intriguing.  Though for the $900 MSRP, I think you could come up with a similar solution that is closer to the fuel needs of your EA71.

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44 minutes ago, carfreak85 said:

Just looked up the kit on Holley.com.  It's rated at 350 N/A hp, but in the Q&A section they say they have tested it down to ~100 hp.  That's still a solid 30+ hp more than even the healthiest EA71 ever made, so it would probably work, but you'd be running pig rich all the time.

I would pass on it, but it is intriguing.  Though for the $900 MSRP, I think you could come up with a similar solution that is closer to the fuel needs of your EA71.

Possibly use a throttle body from anther small 4 cyl engine and a megasquirt system?

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48 minutes ago, carfreak85 said:

Just looked up the kit on Holley.com.  It's rated at 350 N/A hp, but in the Q&A section they say they have tested it down to ~100 hp.  That's still a solid 30+ hp more than even the healthiest EA71 ever made, so it would probably work, but you'd be running pig rich all the time.

I would pass on it, but it is intriguing.  Though for the $900 MSRP, I think you could come up with a similar solution that is closer to the fuel needs of your EA71.

Take all advertised HP gains with a grain of salt.Too many variables to actually justify the gains on all engines. Do you have the link so we can all peek at it?

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yes here is the link I have

https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_2300_2bbl/sniper_2300_2bbl_master_kits_with_fuel_system/parts/550-849K

not sure about the issue about how it would be running rich all the time as the system has an internal fuel regulator. according to Holley.

I have considered using a Subaru fuel injection system that I pulled off a 1.8 l engine but that presents a host of problems also

2015-09-29_09-40-47_652.jpg

2015-09-24_15-59-12_923.jpg

2015-09-29_09-41-17_471.jpg

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2 hours ago, subarujim01 said:

not sure about the issue about how it would be running rich all the time as the system has an internal fuel regulator. according to Holley.

 

That will regulate the fuel pressure going to the injectors. The problem comes with the fact that it has 2 100lb/hr injectors, when you turn down the duty cycle on those enough for a 1.6l engine, they will not have very much resolution (how much is dependent on the processing power of that little ECU).

https://fuelinjectorclinic.com/flow-calculator

Punching some quick numbers (entering 2 cylinders, as it seems to be calculating it based on one injector per cylinder), assuming you make about 75hp at the crank, You should be running about 20lb/hr injectors, but that kit comes with 100lb/hr units. If the Injectors can be replaced with smaller ones, it would probably work very well.

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Thanks that adds some clarity.

I will talk to Holley about possibility of changing the injectors to better match , that is if the onboard ECU can not adjust the injectors.

Depending on the cost it would than make the system they have really adaptable for a wide range of applications.

If Holley can not/will not work with me, than maybe the link you added (thanks) will point me to the right person/company to help out.

either way it seems like an better way to go then modifying the Subaru FI system I have.

Edited by subarujim01

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Well one of the reviews said he put it on a 1.8L toyota motor ...

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You might even find a 4 cyl 94 Chevy S10 truck one barrel throttle body & make an adapter plate, use a mag pickup EA distributor & lock the advance, TBI harness & 7747 ECM from a small block V8 90-91 Chevy truck. Add a 4 wire heated O2 sensor in exhaust wired to relay power/ign started.

Get map sensor, ignition module & coil, etc from the 94 S10. 

Strip down harness to basics, tie both injector pigtails in parallel. Single barrel, single injector. 

https://www.pirate4x4.com/forum/chevy/432269-working-stock-tbi-harness-conversions-picture-intensive.html

There is far more support for modding GM V8 ECMs on forums like Gearhead EFI for remapping the prom. Its been done many times.

Data logging first after you get it running: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?7559-1991-chevy-dually-chip

http://www.gearhead-efi.com/Fuel-Injection/forumdisplay.php?25-Old-School-EFI

http://www.gearhead-efi.com/gm-ecm-pcm-conversion/tbi-efi-conversion.html

Example, a TBI converted Toyota 4X4:

https://www.pirate4x4.com/forum/toyota-truck-4runner/895975-22r-tbi.html

And on Binder planet:

http://www.binderplanet.com/forums/index.php?threads/toyota-22r-gm-tbi.116623/

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13 hours ago, nipper said:

Well one of the reviews said he put it on a 1.8L toyota motor ...

It's certainly possible. It all comes down to how fast the injector actuation is, and how quick the ECU processor is. That pump and injectors are certainly considerable overkill, but that doesn't mean it can't work on a smaller engine. But that probably is the only big hurdle.

 

Might be able to shoot a quick message to Holley and see if they think that hardware would work on an engine this small or if they can supply smaller injectors. Probably a quick answer for someone that knows.

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I pulled up the full Holley manual to see what the different Ecu setting and possible modifications would be

page 65 talks about the fuel injector flow but indicates it can not be changed.

except it indicated that the ecu internally adjusts it based on the engine displacement.

which seem the indicate that it could work on the 1.6L engine I have in my 1978 Brat.

https://documents.holley.com/techlibrary_199r11321.pdf

The weber adapter plate will work just fine with the Holley.

I really do not like the idea of cobbling together a bunch of modifications.

If I wanted to do that I could get a complete 1.8L or 2.0l EFI crate engine and modify the extra engine support member I have laying around.

as well as the extra gas tank  I have to set up the return fuel line and install the in tank fuel pump. 

I did not get a chance to call Holley yet and speak with them about the injector variability but will do as soon a I can .

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I have another question?

Can anybody tell me exactly when Subaru (in it's wisdom) switched the Valve design of the 1.6l engine from the Manually adjusted valves found on

my original engine to the Self adjuster type found on the 3rd used engine I got in 1993 to replace the 2nd one with.

the old engine design required constant adjustments and if not done resulted in major problems. 

Back in 1982 a shop wanted over $2000.00 to rebuild original, but back than I found I could get used engines from Japan for as little a $145.00

so it was easer to just replace the short blocks.

 

  

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On 3/9/2019 at 11:04 AM, subarujim01 said:

except it indicated that the ecu internally adjusts it based on the engine displacement.

which seem the indicate that it could work on the 1.6L engine I have in my 1978 Brat.

Yes, that's how fuel injection works. The ECU opens the injectors for varying amounts of time (the flow rate of the injector and pressure behind it determines the volume of fuel that passes through in that time) depending how much fuel the engine needs for that revolution. A programmable ECU can further be adjusted to accommodate different engine sizes and other variables (like forced induction).

The question is if the ECU and Injectors are capable of accurately opening for a short enough time to supply a small enough amount of fuel to run that efficiently. I wouldn't bet either way, but it's enough of a question that I'd want an answer before I plopped down over a grand.

 

On the top of the page, is this text "ASK OUR EXPERTS: 1-866-464-6553". I bet a person could call that, and ask if the Sniper EFI 2300 can control a 1.6l 4-cyl making about 75hp. And they'd have a real quick answer for you.

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3 hours ago, Numbchux said:

The question is if the ECU and Injectors are capable of accurately opening for a short enough time to supply a small enough amount of fuel to run that efficiently. I wouldn't bet either way, but it's enough of a question that I'd want an answer before I plopped down over a grand.

On the top of the page, is this text "ASK OUR EXPERTS: 1-866-464-6553". I bet a person could call that, and ask if the Sniper EFI 2300 can control a 1.6l 4-cyl making about 75hp. And they'd have a real quick answer for you. 

Thanks I am calling them now.

any info on the valve question? I have not been able to identify by any numbers on the block just what year the engine was built.

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I talked to the Holley expert and the answer was YES the ECU is capable of metering down to very small flow rates and controlling the 1.6l 4 cyl engines

As an example he said some large engines like my 1973 dodge 440 motorhome at idle low RPM's only require about 2-4 lb/hr.

The ECU adjusts out the injector bounce to compensate and fine tunes the flow resolution.

He also indicated the system is being used successfully on 1.9 l VW Wasserboxer engines the air-cooled 1.6l boxer as well as the small BMW's.

So my puling the trigger maybe closer.

Now I can look at the fuel delivery systems what makes the most sense.

Fitech's command center, edelbrocks efi external sump tank system, or Holley's in-line system and see how to add a return fuel line.

I will need to look at the spare fuel tank I have to see will work best.  

 

 

Edited by subarujim01

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57 minutes ago, subarujim01 said:

As an example he said some large engines like my 1973 dodge 440 motorhome at idle low RPM's only require about 2-4 lb/hr.

Yea, an engine uses the smallest amount of fuel at idle. So if your 440 uses 2-4 lb/hr, the EA71 probably uses about .2 lb/hr.

BUT, if they say it can handle it, than I wouldn't worry about it.

 

No, I don't know of your valve question. I have zero hands-on experience with stuff older than EA81s (and even that, just barely).

Yea, the fuel system is relatively simple. I don't know those kits at all, but converting it to a high pressure system is relatively straight forward. Just make sure everything's rated for high pressure, and you have an adequate return....

 

 

Thanks for following up after calling them. It's good info. Assuming you end up making the conversion, start a new thread with some information on your setup and I'll link it in the FAQ

Edited by Numbchux

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