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the EA82 manifold and hitachi swap (onto EA81 block)


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so... people say EA82 manifolds work on eA81 cars.

 

and the mounting area for the carb is slightly larger... so of course if I was to put on a weber, I would want the EA82 manifold just because it's a little bigger.

 

but until then, I plan on using the 2bbl hitachi on the manifold ($30 from JY) which I am going to pull tomorrow about 9:00AM.

 

I've heard there may be some issues with the carb switching over for the ECU (yes, my '88 hatch has a 2bbl ECU controlled feedback carb)

 

but I'll know the exact details of:

1. If it will work at all

2. How much work it will take to swap

3. How much better the EA82 2bbl hitachi is

 

this is all fun to me, may not be to someone else, but I think it's sounding more fun by the moment. *plus* I'm going to clean the manifold and paint it rally blue. cool.

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DO IT TO IT! :) Let us know if it works. It should run, theoreticly speaking.

 

Just make sure it doesnt leak at all. Might want to pull the EA82 carb off, maybe install new gaskets, and use new gaskets when you mount it to the block. You can get a sheet of gasket paper for like $3.

 

Take pix, and let us know if it works.

 

-Brian

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you could just swap the whole ea82 manifold and carb in one piece, that is, if you know the ea82's carb is good. you wont have to hook up all the feedback stuff to work, but the ecs light will always be on.

 

to put the ea82 manifold on the ea81, it might be in the way of the distributor.

you can take the mounting tab for the dist and mount it upside down, flip the dist body 180 deg to clear the water neck. when doing that, with the dist body backward, keep the rotor pointing like it was. because the disty is backwards, connect all your plug wires backwards to the cap, so they are in line with the distributor.

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Jon has been workin on it since 5:30 and its 9:30 now. It involves bending disty vacuum adavce line connection, cuttin thetab on the manifold so it clears the disty, cuttin the metal heater hose connected to the manifold so it would clear the oil filler neck and removing a small piece of the alternator bracket so it will clear the manifold. Other than that, he's doin a great job on it. GO JON GO!!!

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okay, so here's the story.

 

By close inspection, the EA82 carb is a couple of things.

 

Bigger

Less confusing

Not with as many vacuum lines

 

I haven't measured the difference between the size of the barrels of the two carburetors, but it's definately evident that the EA82 carb is WAY bigger. (like 4mm bigger)

 

the base of the carburetor to where it bolts to the manifold is relatively the same shape, only longer. the actual manifold itself looks beefier, but a little bit more simple...

 

As for the thermoswitches, I've taken all of them off. Although without them my ECU will want to tell me something is wrong, I'm going to trick my ECU into thinking it has them... use the ones from the EA81 manifold only not actually working, just plugged into the ECU to tell it they are there and on.

 

The main three wire connector (three female inputs) has one for the choke, one for the antidieseling solenoid, and one for the power valve. The EA82 has four wires... the same, only the antidiesling solenoid has two wires, a lead and a ground. I've wired the ground to the body of the carburetor and am taking the connector from the carb of the EA81 to match the three prong of the ECU's connector. I'll get pics as soon as I can, but it's not as complicated as it all sounds.

 

in the end, this thing should be pimpin. bigger manifold, less vacuum lines running all over the place, new idle solenoids (not making noise), a bigger carb, bigger jets, and the sight of "Ford Red" or what is about the equivalent of STi red on a manifold.

 

Can't wait to get the alternator bracket done. then there should be no obstructions in the way of the manifold... then hook up a couple things. EGR valve is disconnected, and head that has EGR hook up is blocked off. I run 92 octane gas, so this shouldn't be a problem, even at 8 to 12 BTDC.

 

brake vacuum line

two coolant lines, one from the block to the thermostat housing..., one from the manifold to the heater core.

gas line in, gas line out

three/four vapor canister lines (this will be the interesting part, I need to relocate the canister.

and I need some vacuum caps.

hook up my special SPFI hose intake system. includes all of the PCV system components, wired correctly.

 

Sound like fun to anyone?

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well, it's not going as planned, but it's better than... NOT going.

 

As soon as I had gotten everything to the point where I wanted to test the engine, it ran a bit, ran pretty muscley, with what sounded like some vacuum problems.

 

turns out after that, I went to start it up again, and it wouldn't go... turned good, but the disty died. So I got that replaced, and I just need to block off some manifold stuff and get a new heater hose for the manifold....

 

MMMMMWWWWWWAAAAAHAHAHAAAAHHHHAAAAHAHAHAHAAAHHHHAHHHAHAHHAHHAHAHHHAHHAHAHHAHAHAHAAHHHAAAHHAHAHHAHHAHHAAHAHHHHAHAAA

 

It's a much bigger carb and a little beefier manifold, on top of this, this is my first carb OR manfiold swap. cool.

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  • 10 months later...

Non-feedback carbs were availible for EA81's too.

 

The design of the EA82 Hitachi is much better than the EA81 Hitachi in my opinion.

 

John never did get that thing running... he swapped back to the EA81 Hitachi, and ultimately the car got parted out.

 

I beleive the death blow to it was the EGR pipe not fitting properly when the EA82 manifold was synched down. Ended up breaking one of the manifold bolts off in the head, and then it got real ugly from there - swapping heads out, and blowing the HG's several times.... suffice to say the engine never ran right again. It's now in my possesion, and torn down completely - that's why I know the history of this experiment....

 

GD

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  • 5 years later...

I know this is a dead thread and the OP's project failed, but I was just curious

if this would be possible without the EGR carp.

 

Take an EA82 intake and hitachi non-feedback carb and bolt it on.

Would I need a different disty, or would the EA81 disty suffice for the carb

setup?

I've been looking for a way to upgrade my intake without having to go the

weber route or FI, unless I find an EA81T w/associated parts to use.

 

Its not necessary as my EA81 carb is still working great, but I was just

wondering if it was a viable option.

 

Twitch

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I have a solid lifter EA-81 with a manifold and modded disty from a carbed EA-82 on it. It be running a Weber.

 

Main problem is clearence for the disty, there's a few things in the way in that area.

I also had to mod the alt mount bracket some, but not real sure if it's needed for every engine.

EA-82 lower radiator hose is a "trim-to-fit" for the upper hose.

SPFI style EGR valve.

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It doesnt work with the ea81 Power Steering pump.

 

Its alot easier with just the alternator and not the A/C compressor.

 

Well I don't have to worry about either of those... :grin:

I just have a GM alt on the front that sits a little further forward than the stock

alt.

So my next performance upgrade will probably be an EA82 intake and weber

carb.

After I poor man polish the intake and tune the weber carb when I get it.

 

Twitch

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