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EA-82TT Engine Management Swap

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on the adjustable cams however, would it of just been easier to slot the holes rather than using the cam inserts?"

 

Answer me this. I was told, "the answer is easy, if you take it logically."

 

 

How would you build a SLA, (solid lash adjuster) for this motor? I know how I'm going to do it.

 

Only thing holding back 8 K rpm is valvesprings. We'll see what it will do tho.

 

Doug

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Just out of curiousity, on the right side head, particularly the cam carrier where's the disty going?

 

and i take it those aluminum spacers for the intake you'll be milling to accept injectors?

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Just out of curiousity, on the right side head, particularly the cam carrier where's the disty going?

 

and i take it those aluminum spacers for the intake you'll be milling to accept injectors?

 

What he said. Coil on plug might be a problem, we'll see. I have clearance problems with #1 and #4 spark plugs.

 

The intake. Injecter bungs need installed. I want the center section removable (unbolt and adjustable for different head block combos). Squared up like it is, the runners are equal length. They will be 44 mm inside diameter, now the tubing is 41 mm IIRC.

 

 

I decided today when I do it, I'll take the whole thing to a fabrication shop. I figure a couple hours labor in the hands of someone who knows what they're doing will square it away. I ground through that one runner trying to get enough clearance for the turbo.

 

The thermostat threads are borked. And I don't like where it sits, too close to the runners. A stock EA T part won't fit there. The water crossover bungs are too small for my use so the whole thing is in transition still. But it will work out.

 

I almost cut the stat housing off today to start over. Mabie tomorrow when I cut the runners off. Portable band saw.

 

Doug

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think about it, 16 valve, direct port, dual port exhaust....:slobber:

 

AND i bet it doesnt crack between the valves. paired with MLS headgaskets and ARP head studs, there would be no limit on the EA82.

 

I'm curious to see how it would hold under heavy boost tho.

thing I would do is cut those intake things shorter and weld the intake tubes to that. rather than using the clamp style connector thingies(my mind is not functioning well today.)

 

 

EDIT: Email sent to Neil Hintz(sp?) the original designer. asking what is the current status of these heads.

Edited by rpholz

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think about it, 16 valve, direct port, dual port exhaust....:slobber:

 

I'm curious to see how it would hold under heavy boost tho.

 

Ha. Well, I'm not going to Lock an Load this "B" motor. I don't want to hurt the shortblock. I've got some time in it. The rods aren't "that" good as is.

 

"A" motor, different story.

 

Doug

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picture.php?albumid=293&pictureid=3346

Genuine Subaru turbo to head coolant return hose and Mickey Mouse. That's as good as it gets. Roll pins are common size just different lengths to camshaft and crank sprockets.

 

 

picture.php?albumid=293&pictureid=3344

 

 

 

picture.php?albumid=293&pictureid=3345

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All right, here's what I've got. My first spring loaded adjustable solid lash adjuster. You tell me, what would you call it?

 

It's installed on #1 exhaust valve with a checker spring and valve rocker.

picture.php?albumid=293&pictureid=3351

 

I removed this stuff from the HLA. That little spring is a Genuine Subaru installed magnet. This one isn't near as strong as a new magnet.

picture.php?albumid=293&pictureid=3356

 

 

 

 

picture.php?albumid=293&pictureid=3353

 

 

 

picture.php?albumid=293&pictureid=3354

 

Here's what this version is made of. I did some measuring, and stripped the HLA to the body, bottom cup and top plunger. Installed a grade 8 spring washer under the HLA. 4 pieces, parts left out cost nothing. Or I can just shim the HLA as I have o ring and studs on the cam cases. You can see some of the contact pattern on the valve rocker. The actual contact pattern is important to keep in mind here.

 

Doug

Edited by Quidam

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Defeats the purpose of solid lash adjusters if you have a spring in it. :rolleyes:. The whole point is to not drag on the cam - that's the one important benefit to solid lifters. There is no good way to do solid lash adjusters on the EA82 because you can't easily limit the play in the system to between the follower and the valve stem - not without a spring under the cam lobe follower to keep the follower in 100% contact with the cam lobe which there isn't room for.

 

You are making too many changes at once without testing them. No science and all speculation. You risk failure from multiple areas and there won't be a reliable sequence of changes that you can go back to for failure analysis.

 

GD

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picture.php?albumid=293&pictureid=3355

 

The pistons will be ceramic/silica coated Genuine Subaru 7.7 1. Final CR will be closer to 8.0 1.

 

The cylinder walls are quite thick. Anyone who says these block/cases shouldn't be bored doesn't know what they are doing.

 

Doug

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So that calls for a good, safe, adjustable rev limiter built into the engine management system. Don't know exactly what that will be. Adjustable 7 to 8 K rpm would be nice.

 

One knock sensor for tuning, I'd like to have one for each cylinder while we're at it. :)

 

Knock senser will probably be unplugged on actual drag strip runs.

 

Doug

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Is the EA82TT still using it's turbo? 9.5:1 is high for an older turbo charged engine, normally people lower to compression and increase boost. If you run your own ignition, and timed port injection system, it might hold. You should use larger head studs if you plan to run it much over 6 psi for a great amount of time, (more than a few seconds). 12 psi @ 9.5 makes a EA82T at 90 hp go to 219hp tripling the pressure in the combustion chamber.

 

To ansuwer your question, an STI would have the best control system. Thats what you should use, cost more than a used RS, but thats what you need. Their is a post about Stand alone ECM's in an XT it would help you a lot.

 

I hear you. E 85 or better for fuel tho. When it comes time for head studs easiest thing to do is go over size from stock, and there is room, and drill the block. Find a cooperative stud manufacturer to pull two different lengths that fit from inventory. No custom studs that way. They just have to fit under the cam cases with a conical spring head stud washer.

 

Where is that XT stand alone article?

 

Doug

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well ive gotten no reply back on those heads,

 

and just outta curiousity have you accounted for steering with the turbo right there?

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well ive gotten no reply back on those heads,

 

and just outta curiousity have you accounted for steering with the turbo right there?

 

I'd love to torque down a set of those on the "A" motor. But shipping is killer and you know they aren't cheap. Custom cam of my dreams, lol.

 

The steering, no problem with the distributor out of the way, and if so inclined, I'm not all that concerned with something sticking through the hood.

 

Doug

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The cylinder walls are quite thick. Anyone who says these block/cases shouldn't be bored doesn't know what they are doing.

 

The cylinder walls are just liners - they are actually quite thin. The liners are cast in place below the deck height and while the block can be sleeved, the cost is very high. Boring these without proper equipment can be a problem - it can cause the liners to shift in the bore. It *can* be done - but it's not cheap to have it done the right/safe way. And you can't bore them very far because the liners are only a couple mm thick.

 

GD

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well ive gotten no reply back on those heads,

 

Trust me - if you have to ask - you can't afford those heads.... and "shipping" will be probably 5% of the cost or less - if you think "shipping" is stopping you.... get prepared for the sticker shock of your life when/if you get a quote. Very likely he didn't reply because he knows it would be pointless..... A "cheap" engine to the experimental aircraft guys is $10,000. With the complexity of the build required to use those DOHC heads (belt, tensioner system, oil pump drive, etc) he probably isn't interested in selling them seperate. Likely it would be part of a conversion "kit" that's going to cost more than half a dozen old EA82 running, driving vehicles, or it's going to come as a complete finished engine for $15,000 or something rediculous. What's the point in that? Just buy a WRX and move on.

 

GD

Edited by GeneralDisorder

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The heads...I have a PDF and people have done a lot of talking about them. I have used that aren't cracked, and I can fix a NOS head so it probably won't crack. Unless it's overheated and old Subaru is one of the most overheated engines on the planet, IMO.

 

Cylinder Head Cracks On

1985-92 Subaru 1.8L OHC & OHV Engines

 

AERA members have reported cracked cylinder heads on 1985-92 Subaru

1.8L OHC and OHV engines. These cracks occur in the combustion chamber of

the head between the valve seat inserts (see illustration). The cause of these cracks is usually related to an overheated engine.

 

It has been determined by Subaru that this crack does not leak coolant into the chamber and the cylinder heads should not be replaced. Extensive testing indicates that under pressure testing, the heads do not leak unless the cracks are termed extensive Pressure testing is still advised to assure your customer of the heads integrity. Checking both valve seats for looseness is also necessary as insufficient press fit may allow the seat to move during engine operation.

 

A modification to that area of the casting was made during 1991 production to chamfer and increase the distance between the valve seats. That change has reduced the number of heads that crack.

 

Some AERA machine shops remove the valve seats, weld the cracked area and reinstall valve seats to give the head a more acceptable cosmetic appearance.

 

The AERA Technical Committee

 

 

January 1996 - TB 1300

 

 

##END##

 

No cracks here, and the "chamfer" is gone. No hot spot. Gen 1 head.

picture.php?pictureid=3348&albumid=293&dl=1319518580&thumb=1

 

This head is robust by design with very good execution. People still manage to crack these too.

picture.php?albumid=289&pictureid=3347

 

Some people can tear up an anvil.

 

Doug

CYLINDER HEAD CRACK BETWEEN THE VALVE SEATS

Article Text

1989 Subaru DL/GL/RX

For Craig's Shop

Copyright © 1998 Mitchell Repair Information Company, LLC

Wednesday, November 05, 2003 07:13PM

ARTICLE BEGINNING

TECHNICAL SERVICE BULLETIN

CYLINDER HEAD CRACK BETWEEN THE VALVE SEATS

Model Subaru L-Series & Loyale (1.8L MPI & SPI OHC Engines)

Group Engine

Bulletin No. 02-88-93

Date February 5, 1993

NOTE: Do not replace cylinder heads for a crack between the intake

valve seats.

Some cylinder heads may exhibit cracks between the intake and

exhaust valve seats. These "bridge cracks" do not cause coolant

leaks or result in valve seat movement. "Bridge cracks" are cosmetic

in nature, and do not justify replacement of the cylinder head. See

Fig. 1.

Production Changes to Prevent Bridge Cracking

1. A chamfer was made between the valve seats and the cylinder

head.

2. Distance between the intake and exhaust valves was increased.

This condition does not affect the integrity or durability of the

cylinder head nor the operation of the engine.

Fig. 1: Cylinder Head Crack

END OF ARTICLE

Edited by Quidam

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Trust me - if you have to ask - you can't afford those heads.... and "shipping" will be probably 5% of the cost or less - if you think "shipping" is stopping you.... get prepared for the sticker shock of your life when/if you get a quote. Very likely he didn't reply because he knows it would be pointless..... A "cheap" engine to the experimental aircraft guys is $10,000. With the complexity of the build required to use those DOHC heads (belt, tensioner system, oil pump drive, etc) he probably isn't interested in selling them seperate. Likely it would be part of a conversion "kit" that's going to cost more than half a dozen old EA82 running, driving vehicles, or it's going to come as a complete finished engine for $15,000 or something rediculous. What's the point in that? Just buy a WRX and move on.

 

GD

 

I am just curious and am trying to find out more about them, damn GD get of your high horse.

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