Major Differences between EA81 and EA81T?

[slideshow86]

Well on my hunt to find a solid eng for my brat, i happened to come across a few crate eng's. I found a total of 3 EA81T's. I would love to do the spfi turbo swap, But need to get this thing going. I shouldnt have any issues if I bought one of these and pulled the intake and stuff and swapped it out for my carbed stuff, right?

 

What are the major differences between the two?

 

BTW i can get these crate eng's for 400 each, if anyone is interested. Im sure we could get a much better price if we bought all 3. He said he needs them gone.

[Reveeen]

I would have no issues if I bought one of these and pulled the intake and stuff and swapped it out for my carbed stuff, right?

 

If lack of power due to less compression could be called an "issue" then maybe these are best left right where they are.

[slideshow86]

Wow, bad day at work?

 

Thats one way to tell me it has lower compression.

[Reveeen]

Wow, bad day at work?

 

Just a LONG one.

 

Being an old man, let me assure you, when you find that "pristine" Indian/Harley/Vincent in a barn there is usually a pretty good reason it is still there.

 

There were pictures posted here about a year ago of rebuilt/crate motors in the scrap because no one wanted them.

 

Aluminum scrap contaminated with iron is worth 2-3 cents a pound.

[slideshow86]

Well, I called all the local eng importers and not one had an ea81 in stock. I was told that once they are gone, they will not order more. One place had one but they wanted 800. I finally foud an importer that had the 3 ea81T's. I have bought many crate eng's and never had issues. If i could, i would just rather take on the whole turbo spfi swap. Infact, im going to start looking into it.

[hatchsub]

Im not sure I understand what your trying to do. You say turbo SPFI swap. What are u refering to? The EA81T is a MPFI motor. As mentioned above it has less compression but since its turbo it was rated at 95 horsepower compared to 74. 400 for a crate motor doesnt sound that unreasonable.

[Reveeen]

Well, if you were thinking "green?", a low compression engine has it's uses:

 

http://en.wikipedia.org/wiki/Wood_gas

 

Of course, something like this may be easier:

 

http://www.utterpower.com/10hp_chevy.htm

 

(I'm just kind of kidding and pulling your leg here!)

 

i would just rather take on the whole turbo spfi swap. Infact, im going to start looking into it.

 

At the end of the day, if you bought a "new" turbo motor, and changed the pistons, using the heads most suitable for your existing stuff, you would probably be close, cost wise, to rebuilding what you have (unless there is a hole in it).

This is why they seem to prefer to adapt EJ engines into the older vehicles, depending what you pay for a very rusty early Legacy (I bought a not so rusty turbo one for $400 that is a daily driver), a $200 adapter, and a bunch of work, you end up with 145ish HP in a bullet proof situation.

[cawain]

where are the EA-81Ts? I wish I ad one I woud just block off the injector ports, install a carb and go. So you got lower compression, so what. you got hyd lifters and you don't have to adjust them. I have one out back I would do that to, But I have the whole car and I am going to make a trike out of it. It should get up and go with the turbo and mpfi.

 

 

Well, I called all the local eng importers and not one had an ea81 in stock. I was told that once they are gone, they will not order more. One place had one but they wanted 800. I finally foud an importer that had the 3 ea81T's. I have bought many crate eng's and never had issues. If i could, i would just rather take on the whole turbo spfi swap. Infact, im going to start looking into it.

[GeneralDisorder]

EA81T has almost the same HP as the EA82 SPFI (5 HP less) - just drop in the EA82 SFPI instead and be done with it - EA82's will fit with only minor adjustments in the EA81 bay. It will have more power than a low-comp. EA81 with SPFI for sure. Better econemy and easier to find too.

 

GD

[GeneralDisorder]

Im not sure I understand what your trying to do. You say turbo SPFI swap. What are u refering to? The EA81T is a MPFI motor.

 

You actually could do this and it would work. The SPFI manifold bolts to the EA81T heads - you just wouldn't use the MPFI injectors (in the heads), and you would want to run some sort of management or piggyback as the SPFI ECU is known to have issues with positive manifold pressure situations. Also you would want a second injector as the stock injector won't supply enough fuel at WOT with a turbo.

 

GD

[slideshow86]

Very sorry guys. My wording is wrong, I didnt know if it was spfi or mpfi. I really dont know much about theses subies, other than what I own. I just started in these ea81 MY cars. I have never seen an ea81T and untill 2months ago, I had never seen under the hood of an ea81 MY.

 

I can get an ej22 crate eng for $500

 

Looking for a legacy now.

[one eye]

Very sorry guys. My wording is wrong, I didnt know if it was spfi or mpfi. I really dont know much about theses subies, other than what I own. I just started in these ea81 MY cars. I have never seen an ea81T and untill 2months ago, I had never seen under the hood of an ea81 MY.

 

I can get an ej22 crate eng for $500

 

Looking for a legacy now.

 

Talk to Scott in bellingham he might have a trick or two up his sleeve.

 

Jeff

[slideshow86]

I think If I were going carbed. I would get an EA81. I want to go all or nothing. Not knocking the ej carbed. But I just think I can pull it off.

[TheSubaruJunkie]

Ok lets focus on your original question...

 

"Major Differences between EA81 & EA81T"

 

The biggest difference between the two, other than the turbo of course, is the fuel delivery. EA81 is carburated. EA81T is MPFI. That being said, the MPFI needs a ECU to run it propperly.

 

Can you swap the intake manifold and run a carb on it... maybe. Will it ever run as good as a regular EA81... no. Whynot? Well cause:

 

1) Lower Compression: The EA81T has a lower compression ratio to make up for the boost. "Big deal" you say? Yeah, it is a big deal. You think a EA81 is underpowered now, remove compression on not just one, but ALL cylinders and you have a lawnmower engine powering a stationwagon.

 

2) Fuel Injector Bosses: The heads are different, they have fuel injectors in them and you will need to remove and plug these. You can do it, but just another pain in the rear.

 

3) Distributors: The EA81T has a special type of distributor (cannot remember the technical term off the top of my head) but it will not run propperly. So you will need to use your standard EA81 distributor.

 

There are plenty of other alternatives. EA81's are not that hard to come by. Maybe we should be asking why you are looking for a new EA81 in the first place?

 

-Brian

[hatchsub]

crazy thought i just had. Has anyone swaped the heads an intake from a Turbo EA81 onto a N/A block? Then run some sort of computer such as megasquirt? That way you would have an N/A MPFI EA81. Higher compression N/A block and pistons and MPFI should mean its pretty quick compared to carb.

[Leeroy]

crazy thought i just had. Has anyone swaped the heads an intake from a Turbo EA81 onto a N/A block? Then run some sort of computer such as megasquirt? That way you would have an N/A MPFI EA81. Higher compression N/A block and pistons and MPFI should mean its pretty quick compared to carb.

 

I have always wanted to try this, using turbo heads on an N/A block and an aftermarket computer. Unfortunately EA81Ts are like hens teeth here in Australia. There is one for sale at the moment for (from a wrecker) $1500, engine only (no turbo or computer???).:-\

 

From what I have read here on the board SPFI is a much better (simpler & cheaper) option in the US.

[TheSubaruJunkie]

Yeah, i had that idea more than once. a MPFI EA81 would be great off-road. Could probably still run it all off the stock ECU.

 

I also had an idea to run the carburator on the motor and use the injector bosses for NOS injectors

[slideshow86]

Maybe we should be asking why you are looking for a new EA81 in the first place?

 

-Brian

 

 

-Well I had a long post, but somehow deleted it :-\ , heres the brief version-

 

I pulled compression on #3 cyl, to find it was very low (to find out later, I may have pulled compression incorrectly)

 

I had put all new plugs in it and had to run it long enough to show signs of what its doing. #3 spark plug has no signs that that cyl is firing, it still looks brand new. It is fuel soaked and it I think it is getting spark. ( I am assuming its getting spark, B/c when I had the eng running and pulled the sparkplug off #3 cyl it didnt change note of the engine even a little bit. It did shock the hell out of me though, which makes me think im getting spark)

 

People suggested that I may have a stuck valve. Followed what other said and pulled ATF and Seafoam through the intake. It did do one thing weird. After I got done sucking either fluid in there, It would leak out of the pass side exhaust port. Kinda coming out the gasket and down the manifold. Would this be a stuck exhaust valve in 3? It not being able to close all the way and leaking the fluid? (and compression) Same poor acceleration, It didnt fix it. I didnt re-pull compression though. This was all last resort for just pulling it out for somthing I know works. I just dont have the time or the help to mess with it. I just want it to run. When it runs, I can work on my ej swaps.

 

Either way, this thing has a very loud tick. Almost knock. It gets worse as the enging warms up.

 

My main issue is lack of help. The person helping me works 2 weeks on 2weeks off. I am just trying to trouble shoot this thing by my self and its hard to pull compression and test for spark when its just me.

 

OOps forgot all my links to all the threads going right now for my car

 

http://www.ultimatesubaru.org/forum/showthread.php?t=85550 Weber fixed now timing issues 85 Brat

http://www.ultimatesubaru.org/forum/showthread.php?t=85673 Troubleshooting Ea81 fuel pump

http://www.ultimatesubaru.org/forum/showthread.php?t=86206 Help identify my coil...Ea81

http://www.ultimatesubaru.org/forum/showthread.php?t=86114 I cant fix my brat

http://www.ultimatesubaru.org/forum/showthread.php?t=86318 I need a solid ea81 eng in Washington

[TheSubaruJunkie]

A good compression tester should have a valve built in so pressure doesnt bleed off. That way the needle stays at the most pressure so you can crank the motor over then go check the gauge.

 

I recommend removing all 4 spark plugs when You do your compression test. this way the motor will rotate at its fastest. Also, run your test... then remove the compression tester and squirt a few drops of oil into the piston and run your test again. If the results change, chances are you have bad rings.

 

However, a stuck valve is a possibility. If you have a valve stuck open, you would have 0 compression on that cylinder.

 

I know what you mean about not wanting or having the time to mess with these motors. I gave up on my EA81 as well when it was having trouble and went with the EJ22 Wagon I now have.

 

-Brian

[slideshow86]

However, a stuck valve is a possibility. If you have a valve stuck open, you would have 0 compression on that cylinder.

 

-Brian

 

 

Good point. I drove it over to someones house and they were using the tester. All I remember was him saying. Man, oh man, ya you have no compression dude. But I remember hearing a -whhhssst- when he pulled off the tester, so there was compression, some. I think it was like 35 or somthing with the other 3 plugs still in. He has one of those old school testers that have a rubber thing that you hold up to the sparkplug hole, but hay, its better than mine.

 

We did try to drop some oil in the cyl and it didnt change it a bit.

 

Jess

[TheSubaruJunkie]

I had one of those testers and i hated it.

 

spend $50 on a decent tester. Hell, even Harbor Frieght sells a decent tester for $20 that is better than that.

 

I wouldn't trust the rubber tipped compression testers at all.

 

-Brian

[Forkspear]

It did do one thing weird. After I got done sucking either fluid in there, It would leak out of the pass side exhaust port. Kinda coming out the gasket and down the manifold. Would this be a stuck exhaust valve in 3?

 

Either way, this thing has a very loud tick. Almost knock. It gets worse as the enging warms up.

 

Does the tick you are hearing get louder when you give it gas? I bet it is just an exhaust leak where you saw the ATF leaking out of the exhaust port.

[slideshow86]

Oh ya it gets louder. The tick is soo freakkin loud! I was thinking exhaust valve on #3 too.

 

The PO said it ticked really bad. When he got it the PO said it ticked really bad. I just dont know if these 2 guys are retards or just dont know any better? Or if this thing is absolutely beat to hell. One thing, when I got it. It was more caked with mud than I have ever gotten my wagon. Well the under carrage any way. Every mount was shot and both front axles were toast. Both front tow hooks were smashed flat (somehow they spared the oil pan, even w/o the skid plate) So Im thinkin beat.

 

Looks like I have to figure out how to inspect this thing propperly?

[MilesFox]

crazy thought i just had. Has anyone swaped the heads an intake from a Turbo EA81 onto a N/A block? Then run some sort of computer such as megasquirt? That way you would have an N/A MPFI EA81. Higher compression N/A block and pistons and MPFI should mean its pretty quick compared to carb.

 

there actually was an n/a mpfi ea81 in the 84 gl-10. mpfi was offered as a premium but spfi hadnt been developed yet. this is why you can also find na/ mpfi ea82's in 85 gl-10's

 

to go with turbo, either route, you would have cut out or otherwise modify a depressionin the crossmember for the cross pipe.

 

the simplest thing to do to go turbo would be to swap an ea82t with wiring harness, or even a complete ea81 with ea82 engine harness. use 85-86 harness/ecu fo that)

 

otherwise with the amount of work you can go ej

 

if not for all the work, and you want something to drive, just go find any ea82 spfi motor and throw your carb onit and call it a day. you will actually gain compression, and the ea81 intake fits almost the same.

 

just look up ea82 conversions, it has been done a few times. i have done a few myself.

[Turbone]

there actually was an n/a mpfi ea81 in the 84 gl-10. mpfi was offered as a premium but spfi hadnt been developed yet. this is why you can also find na/ mpfi ea82's in 85 gl-10's

 

to go with turbo, either route, you would have cut out or otherwise modify a depressionin the crossmember for the cross pipe.

 

the simplest thing to do to go turbo would be to swap an ea82t with wiring harness, or even a complete ea81 with ea82 engine harness. use 85-86 harness/ecu fo that)

 

otherwise with the amount of work you can go ej

 

if not for all the work, and you want something to drive, just go find any ea82 spfi motor and throw your carb onit and call it a day. you will actually gain compression, and the ea81 intake fits almost the same.

 

just look up ea82 conversions, it has been done a few times. i have done a few myself.

 

You will need to prove that, or no one is going to believe you.

Including me.