It's been done, but let's do it again; EA81 Performance mods?

[markjs]

I love my "new-old" GL, but the one and only flaw is it's underpowered.  I'm not talking a lot, but if I could just get a small gain at low RPM in higher gears it might be worth it.  I'm considering the Weber and plan to do a junkyard tour soon, but cost on that is an issue as I am of extremely limited means. 

 

I did read about an interesting mod to the Hitachi two barrel (which my car has), where the secondary vaccum diaphram is disabled and a wire lever is attached to make the secondaries open sooner.  He mentioned it giving a flat spot somewhere low in the RPM< which is not what I want, but I'm sure that was because of restricted airflow, he did not mention if he was using the stock airbox or not, that I recall.  If anyone knows anything about this mod, I'm very interested?

 

I guess there's also the issue of not having power steering, but I consider that a luxury not a flaw.  Did the 84 GL even have power steering as an option? If so, how hard is the conversion?

 

So yeah, let's have some fun with ideas, and even "it will never work...." cuz I know a whole lot isn't possible on the cheap, but well, that's what we do here isn't it?

 

Thanks, happy Subaruing

[ferp420]

Go with fuel injection from a ea82 and or upgrade your ignition system to a msd style ive had tbe msd cure alot of carb issues and it make it feal like its got more low end but realy its just burning the fuel more efficently it was by far the best doller per dohnut power upgrade i did to my rigs another cheap trick is to raise the carb by puting a spacer under it that allows the air and fuel to mix before the mixture turns the corner while also providing a.higher volume of air right when the throtle opens making the car feel more responsive if you want to spend some money ram enginering makes intake spacers a cat back exhaust would help to a electric fan should free up a few hp removing any extra waight makes a big differance if your gona go in to the motor than port polish and shave both the deck and the heads and new pistons to raise comprestion alittle but remeber each mod only dose a little bit so the more mods the more noticable the new power will be

[GeneralDisorder]

SPFI pistons and a Weber. Stop there because anything more is diminishing returns and carries high risk if you split the block, etc. The SPFI, while nice for year-round cold starts, does not give as much low end torque, and is becoming difficult to get parts for. Redline makes all the Weber parts and will for the foreseeable future.

 

GD

[George1943]

I took the power steering off of an '83 GL wagon to put on my '82 Brat DL. It was a bolt on swap. I don't have 2 of the 3 holes on the front of the head to mount the pump but the 1 that I do have is working just fine. It's been on the Brat for almost 2 years now and no problems. Even on a vehicle this small, PS is nice to have. Also, the Webber upgrade is well worth it. 

[iceageg]

Can't go wrong with the Weber.  If you do split the block the Delta torque regrind is a great deal for the money.  That combination got me alot (by EA81 standards) of low end performance.  Even if you add the SPFI pistons and do all the other stuff that has been tried here you will still struggle to get to 100hp though.  So keep your expectations realistic.

[jono]

Power steering ...think about it for a moment....power ....you really don't want to add something to the engine that is going to rob the engine of any power at all coz a pump will use some of that power you want more of. So, don't worry about power robbing steering.

 

I don't have power steering on any EA81, never did except for a donor that I drove around the block. It was gutless, but may have been due to the auto and worn out condition. I rebored and rebuilt that motor with a cam (requires split the block)

 

An exhaust header/ Y pipe from an EA82 is said to have larger extraction pipe diameter internally

 

So, I believed like you do on the internet, and found I got an extra 10 kph in second and third. I also resolved an issue I got because the cam I selected 20/60 0.235" lift solid cam lifters was a bit too wild for towing small loads - got a bit breathless until I fitted Y pipe. The pipe is a bout 3/4" longer so you really only just push the rest of your exhaust further back a little - unnoticed by any underbody stuff except maybe remake the hanger at gearbox. The join lines up, and ring gasket at rear fits to factory EA81 mid section pipe.

 

All EA82 should have a cat. Tends to quieten things

 

Should be cheapest most cheerful mod you should spend on first

Put want ad for weber instead of buy new?

 

Surely many have upgraded to EJ and have weber kicking about cheap?

 

Has the Hitachi ever been rebuilt? Could be your problem also?

 

Another weird mod I have done, so comes from my experience not www BS, was to fit an upper cylinder lubricant dispenser to the base of the carb of a Ford big six. I used the correct lube in a bottle that fed a dripper with an adjustable drip rate. One litre may have lasted about 10,000 miles from memory.

 

After fitting, I drove about 10 miles, pulled up to stop at the lights, engine was racing with a much faster idle. After a few more miles, same thing, popped bonnet thinking something must have been caught up in the totally mechanical linkages no cable set up.

 

Nope, nothing. Everything was perfectly unchanged, no interference. I had to physically wind the idle down a few hundred revs!

I figured the upper cylinder was indeed get lubricated beyond any claims or expectations. Never tried on a subaru. But another cheap and cheerful mod.

 

But, seriously...if you can find an EA82 donor vehicle to test drive all its components first and feel like a big job - an EA81 body with EA82 driveline difference is one hell of an improvement. Just keep EA81 radiator for its twin tube cooiling efficiency

 

I have done this twice now...still rejecting 12 years of "EJ it" comments

Edited April 4, 2018 by jono

[el_freddo]

Contrary to Jono, I've fitted PS to both the brumbys in our family. Oddly it makes the vehicle feel lighter/sportier - I can throw the brumby through corners heaps easier and haven't noticed a drop in performance.

 

If you doing a bit of a build get the later model heads - the ones with the black rocker covers. These covers could have been changed but generally are not. The later model heads have a larger intake valve.

 

Dizzy: make sure there is no shaft play. This will have a detrimental effect on your timing and thus performance.

 

Cheers

 

Bennie

[GeneralDisorder]

PS uses no engine power unless you are steering. That's how the system works. It doesn't develop any pressure till pressure is required to do actual steering.

 

GD

[Sapper 157]

In addition to putting a weber on there, you could try doing JeZeks custom muffler trick to free up the exhaust. Makers the car breath much better and should give you a little power boost. 

 

But yeah... Definitely get rid of that Craptachi. Take it from me, after fiddling with mine and rebuilding or opening it up probably over forty times, I was never able to get it to run right. So dump that piece of junk and get a weber as your first move. The weber is highly constomizable, modifiable, fixable, simple, and easy to find parts for.its everything that stupid hitachi is not. Just go   http://www.carburetion.com or really anywhere else and you can find every part you will ever need.

Edited April 5, 2018 by Sapper 157

[jono]

Hmm, I still run factory EA81 pea shooter exhaust from Y pipe rear back and my EA82 twin port has no trouble exhausting and is so quiet I can hear my induction ROAR !

[Sapper 157]

Hmm, I still run factory EA81 pea shooter exhaust from Y pipe rear back and my EA82 twin port has no trouble exhausting and is so quiet I can hear my induction ROAR !

Yes... but the theory is that the factory exhaust is restrictive, which causes unneeded back pressure. When the old exhaust system is upgraded so it is less restrictive, it causes a power boost because now the engine is not fighting that unneeded back pressure. That is my understanding at least...

[ferp420]

I have the webber on my vw although its absolutly reliable and works great its not very fuel efficiant i lost around 7 mpg and i dident gain any power but it always runs however mine floods out real easy probably needs a float adjustment or something but ive been running it for 15 years and never touched 1 screw on it since installing it i still say the msd ignition is the biggest power gain you can get for the money i got mine for $100 i know there cheaper than that now it hooks up with no modification just take the wires off the coil hook them to the msd box and the box to power and coil and you have around 10-15% more low end torque it wont increese peek torque just bring it on alot sooner with 30" tires i went fron struggling in 1st gear to being able to do a second gear start with eazy from just adding the ignition box

[Sapper 157]

 

I have the webber on my vw although its absolutly reliable and works great its not very fuel efficiant i lost around 7 mpg and i dident gain any power but it always runs however mine floods out real easy probably needs a float adjustment or something but ive been running it for 15 years and never touched 1 screw on it since installing it i still say the msd ignition is the biggest power gain you can get for the money i got mine for $100 i know there cheaper than that now it hooks up with no modification just take the wires off the coil hook them to the msd box and the box to power and coil and you have around 10-15% more low end torque it wont increese peek torque just bring it on alot sooner with 30" tires i went fron struggling in 1st gear to being able to do a second gear start with eazy from just adding the ignition box

Off topic, but if you lost that much MPG i think something else might be at play. Did you advance your timing enough? Did you follow the mixture control settings properly? Is your jetting correct? After ten years, I’m sure your Weber could benefit from a seal change and a good internal cleaning.

Edited April 6, 2018 by Sapper 157

[djellum]

Yes... but the theory is that the factory exhaust is restrictive, which causes unneeded back pressure. When the old exhaust system is upgraded so it is less restrictive, it causes a power boost because now the engine is not fighting that unneeded back pressure. That is my understanding at least...

 

a motor is basically a big air pump, more air out means more air in.  up to a certain point it will add power but mostly it just changes where the power is at.  sort of like adjusting your timing can move where your power is felt.  if you open it up too much its a power loss because the velocity of the exhaust matters as well.

 

little motors like this generally don't pump enough gas out for a larger exhaust.  open it up a bit and make sure its in good shape, and dont use crappy mufflers or cats, and you should be fine.  mostly it depends on what you will feed it.  if you want to put more fuel in or at a faster rate, you might benefit from a bit bigger pipe.  gas mileage and stock applications probably wont matter much.

 

in general header theory says that the header pipes should be equal length to allow pulses to combine seamlessly, which is much more efficient.  our cars regularly go unequal length, but you might investigate doing an equal length Y pipe.

[jono]

Yes... but the theory is that the factory exhaust is restrictive, which causes unneeded back pressure. When the old exhaust system is upgraded so it is less restrictive, it causes a power boost because now the engine is not fighting that unneeded back pressure. That is my understanding at least...

used to be miy unnerstanding  too !!

Edited April 6, 2018 by jono

[MyWifesWagon84]

Hey guys new here and trying to find my way around. When i can i will post a how to for my mikuni swap. It doesnt have to be done the way i did it but it was cheap. You will need a 45mm mikuni motorcycle carb a bit of 1.5 inch water pipe. The mikuni is about $175 and the rest is dirt cheap. I was able to get mine to run our of the box with the main jets it came with. Ps the bottom end is where almost all your gains are with this carb.

[ferp420]

"Off topic, but if you lost that much MPG i think something else might be at play. Did you advance your timing enough? Did you follow the mixture control settings properly? Is your jetting correct? After ten years, I’m sure your Weber could benefit from a seal change and a good internal cleaning. "

 

I havent touched it at all my vws are just yard art now days i just keep them running to move around the yard

[MyWifesWagon84]

The mikuni in its new home.

[MyWifesWagon84]

The intake the intake elbow freezes on long trips.

[MyWifesWagon84]

Sorry the first didnt upload

[Knucklehead Saloon]

Besides the weber and ignition stuff I also went with an unequal length header and a 2" sports system. The engine comes on the pipe around 3500rpm and makes power right through to 5500. It'll rev to 6100 but just making noise.

 

Next up for me is to port a set of heads and see how that goes.

 

If you search my posts back far enough theres a vid of the pipes/weber and how they sound.

[ferp420]

Port them up get the ports.as close as you can dont worry if there a.bit.off the unequel lenght header makes every ports path diferent anyway so close is good enuff i shortened my valve steams and reground my valves for.better flow and polish the exhaust side the best you can and the cumbustion chamber port match everything and grind the weld bead smooth on the inside of the header after the cat go to a 2" to the muffler and 2.5 out the back of the car in my opinion anyway not worth anything other than ive done it and had good results

[ebarb]

Assuming the hood cutout and carb addition are like the first step towards a MadMax style EA-81. When are you going to cut off the top and mount a giant spear gun into the back seat...or if this were a brat.

[Sapper 157]

The intake the intake elbow freezes on long trips.

Had any induction icing issues with that intake pipe like that? Personally, I think having to cut the hood of the car is quite a sacrifice. I’m perfectly happy spending $70 and getting a more powerful, more customizable Weber 32/36 where I don’t have to sacrifice my hood and don’t have to deal with as much fabrication. You have a cool concept, but honestly I think the Weber is a little more practical. Just my opinion... you can do whatever the heck you want for your car.

[ferp420]

The webber can provide the corect air fuel ratio the makuni carb wont been there did that 20 years ago while you were still sucking tit on my volkswagons swaped to the webber to fix its issues this isent new its its older than you are

Edited April 8, 2018 by ferp420