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head porting!


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FIRST OFF, I'D LIKE TO SAY, FOREVER IN USMB HISTORY, I POPPED THE CHERRY ON THIS SECTION!!

 

:clap::clap::clap:

 

 

 

secondly, went and dug up tycho's (member here) pictures of his ported ea82 heads, just so it would be added to this section. head porting is by far the cheapest bang for your buck to get some decent extra horsepower. all it takes is some sander rolls, maybe an aluminum grinding burr or two of different shapes from mcmaster.com, and a variable speed die grinder, or pneumatic grinder, but not everyone has a compressor that can run one. if you have never done it before, buy a junk warped or cracked head to practice on. then, go read everything you can on it. techniques are the same across the board, you just need to apply it to whichever engine you are working on.

 

 

http://web.me.com/dgiessel/Pictures/misc/ea82t/index.html

 

 

here as well is a cutaway, showing you roughly how much you have to work with when porting these heads. the pictures are ER27 ports, but as we all know, they are nearly identical to an EA82.

 

 

483973_1979670978192_1755971939_n.jpg

 

 

306815_1979670858189_1644575916_n.jpg

 

 

a few links on the topic:

 

http://65corvette.nonethewiser.net/technical/diyport.pdf

 

http://www.allpar.com/fix/holler/head-porting.html

 

 

http://www.allpar.com/fix/holler/head-porting2.html

 

 

so if anyone wants to add to this, or ask questions, ill try and answer the questions to the best of my abilities.

Edited by maozebong
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I can add to this library, I cut some EA82T heads up before I ported mine:

 

After looking into the Vortex Hi-Rise intake (would love to cut one of those up too) I Decided to cut a set of Gen2 heads 'in half' to get a clue as to where the weak parts were and where they can be improved, port flow wise...here are the photos:

 

P30-11-09_1230.jpg

 

P30-11-09_123001.jpg

 

P01-12-09_124401.jpg

 

102_4841.jpg

 

They really do have quite extensive cooling around the IN ports, if only the EXH/IN ports were seperated like these:

(This photo also shows the area behind where the 'triangle' shaped water jacket in the block meets the head, they can be drilled here and allow coolant flow directly into the head)

102_4854.jpg

 

102_4851.jpg

 

Really not much cooling down the bottom end of these heads at all, water jackets don't extend past the siamese exhaust merge:

102_4852.jpg

 

This one shows the bulge where the 'D' section meets the 'O' section:

102_4853.jpg

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cont...

 

Again... Outlet bulges:

102_4850.jpg

 

102_4849.jpg

 

102_4848.jpg

 

IMO the intake ports are quite good (also above), exception of course is the castings for HLA buckets protruding inside

102_4847.jpg

 

I like this cut - it shows the very awkwardly shaped EXH port, the very long valve guide, and the amount of meat that is cast around the HLA buckets:

102_4844.jpg

 

You can see how undercut the seat is in places, also shows bridge crack:

102_4843.jpg

 

These ones also show the shape of the EXH port and quite a bit of material that could be cut out around the guide, which in my opinion could also be shortened:

102_4846.jpg

 

102_4845.jpg

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I suppose I should show you the finished port job after I welded the heads back together...

 

Just Kidding:brow:, done to a different set of heads:

 

103_5112.jpg

 

103_5115-1.jpg

 

103_5094.jpg

 

103_5099-1.jpg

 

103_5105.jpg

 

103_5104-1.jpg

 

103_5103-1.jpg

 

103_5108-1.jpg

 

103_5109-1.jpg

Edited by nncoolg
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No worries I just uploaded my finished port job pictures in the post I had reserved.

 

I think this is another 2 cuts of the ER27 heads you mentioned in your top post I found somewhere a while ago:

head.jpg

100_5783.jpg

I think there were a whole lot of photos originally, but I could never find them all when I went looking, I think the links were down. I remember a lot of yellow superimposed lines, showing the performed cuts??? Perhaps someone has them archived and could add them to this library...

 

Actually, this is the threads I originally saw years ago : http://subaruxt.com/forum/viewtopic.php?f=1&t=7121&p=66398&hilit=+xt6+porting#p66398

and here : http://www.ultimatesubaru.org/forum/showthread.php?t=71766

Edited by nncoolg
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Here's some EA 82 Dual Port heads that I've spent some time on. I bought three solid carbide burrs of different shapes initially. The ones for aluminum, of course. I have an industrial Black and Decker 25000 rpm porting tool I've used and a 21000 rpm unit too...electric.

 

I bought a 6" solid carbide burr to get to those longer ports. I've got a flexible shaft with a drill chuck on it I'll chuck up in the drill press to finish them. That one shouldn't be turned faster than 16000 rpm. I've done it, and it's scary at 21000 rpm.

 

I've got the tootsie roll kit to clean them up and I prefer ball hones to do some of the work. More expensive tho I've done it because it really leaves a nice finish.

 

Anyway, I'll try to get more pics.

 

picture.php?albumid=293&pictureid=3348

 

picture.php?albumid=293&pictureid=3349

 

picture.php?albumid=293&pictureid=3350

 

Doug

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alot of the top portwork guys in the nation are doing this, and with great results:

 

head-porting-1.jpg

 

 

"These Powre Lynz will create somewhat of a variable boundary layer. At low flow demands, the boundary layer constricts, keeping velocity high. This is really good for low end torque and off-boost power. It also keeps the fuel actively suspended in the incoming air stream. Larger droplets will bounce off the sharp edges and scatter away in a dozen or more smaller (easier to vaporize) droplets. Some of the fuel will even stick, radiating out laterally and vaporizing into the air stream. As flow increases, the boundary layer collapses allowing improved breathability.

 

There is a very ugly patch of 12 pitch threads under the valve seat on the short side radius of the intake ports. This really excites the fuel in the vicinity to turn a spray into a light fog. The low velocity area around the manifold gets a 20 pitch thread, while the higher velocity areas get a 16 pitch. Because Bob will be driving his Daytona mostly on the highways, I didn’t use much of the coarse 12 pitch Lynz."

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  • 3 months later...

Hey, been busy working over some heads. I believe I've done 10 EA 82 so far. This is a first generation Dual Port that I got bare, and it had been surfaced .007, no cracks.

 

Still have work to do to the upper left sides of both ports. Get all the line of sight I can. Head will be cut a total of .012 at least.

SubaruEA82DualPortHead.jpg?t=1351294766

 

Here you can see that I cut all the aluminum out all the way to the valve seats. A lot of valve unshrouding going on here.

SubaruEA82DualPortModifiedCombustionChamber.jpg?t=1351294934

 

I'm going to cc a new head and see where it all shakes out. I want a small chamber, but I didn't want all that aluminum in there either.

 

So, a .012 at least cut on the heads, .016 cut off the decks...I'd have to measure again but I think I measured .125 piston to valve on another setup so .097 piston to valve will work.

2.jpg?t=1351294619

 

 

Later

Edited by Quidam
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This is my recipe for an NA engine with no other mods.

 

De-burr the intake ports

 

Polish the exhaust

 

Match port openings to intake.

 

Done. Unless you are adding new cams, you don't want to change the flow rate of the head drastically. And, as noted with an NA (espescially SPFI or Carbed) you want rough texture in the intake ports. If you open up the ports too much, you can actually end up with slower air velocity at a given RPM, and you lose the bottom end power.

 

 

If you are adding new cams......then carve them up like a Christmas Goose.

 

If it's turbocharged (or supercharged) then polish the intake ports like a mirror.

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Just some thoughts. Head porting is expensive, Ram Engines charges $250.00 for a mild EA port job. About $650.00 for a full port and flow bench test. The more heads I do the more I learn and any head under discussion starts with what gen it is and of course SPFI or MPFI.

 

The unfinished sharp edge around the valves is horrific. I've measured this chunk of sharp aluminum to as much as .047 in depth. The sharp edge can form a hot spot and cause problems with detonation, as well as being sharp enough to induce cracks. This needs a roundover at least on all that have it. I've never had my hands on a gen 3 head so I don't know how that looks.

 

The MPFI heads shown here benefit from removal of material in the intake ports. The exhaust ports, bowls aren't too bad. NA engines are under 21" vacuume or so, exhaust is under pressure, so main attention payed to the intake. The head bolt casting and HLA bump removal are gains to be had in #1 and #4, as well as raising the roof and dropping the floor of the port. The #2 and #3 intake ports are much less a chalange.

 

A SPFI and MPFI NA EA 82 only has 4 to 7 hp difference between them, and that's with the MPFI NA XT having a bigger cam.

 

The SPFI head has really good intake ports, and the valve has that back cut, 2 angle valve, but has a badly formed bowl under the exhaust valve.At least gen 1 and 2, due to the EGR boss at each corner of the head extending into the exhaust port.

 

That boss is actually the ugliest part of those exhaust ports. Keep in mind the #1 and #4 ports are slightly shorter than the #2 and #3 ports.

 

These EA engines are going to be around for some time to come, one because of their light weight, reduce, reuse, and recycle comes into play and I can't see throwing away perfectly good parts and aparantly other folks don't subscribe to that either.

 

Ram Engines now sells a 130hp EA 82 with SPFI heads with their new stand alone fuel injection system.

 

I logged about 4 hours porting today. There's a reason head porting is pricey, and it's not for everyone. There is indeed power to be had with EA 82 heads if you pay the price.

 

And the New York Times said, "God is Dead". GD For you gearheads with inquiring minds when it comes to normally asperated tech, look this article over. http://www.enginebuildermag.com/Article/89943/pro_stock_engine_technology.aspx Engine builder mag from a year or so ago. Goes into some interesting detail describing 500ci NA engines now knocking on the door of 3 hp per CI. And they rarely fail.

 

Doug

Edited by Quidam
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all good things, agree 100% about the areas needing attention aye.

 

I think the next set I do I will cut the valve guide and surrounding lump all the way back level with the ports, I reckon with the length of the guides they will be okay like that.

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This assembly has two "pink" first gen drivers side heads. No cracks and I don't have to plug the head for the EGR. With this, no holes are drilled into the exhaust ports. I ported two cracked SPFI heads to get a feel for what to do to these.

Milled012.jpg?t=1350417999

 

I measured the depressions in the exhaust bowl and it's roughly 2mm deep. If I press out the guides, I figure 3 mm removed will clean the exhaust bowls up pretty good. So yea, I've been considering the shortened guide too, and when I get to it, that's what I'll do. I don't think anything bad will happen, and the flow will be substantially improved.

 

Doug

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I've got a set of these MPFI first gen heads. No paint Id on them, in this stage of completion. Carbide burr finish in the ports. I hand worked the combustion chambers with wet/dry carborundum paper. Consequently, their shape hasn't been substantially altered.

 

Of course both stainless turbo valves make them turbo heads. MPFI NA has the stainless exhaust and the backcut intake...that's not stainless.

SubaruEA82DualPortMPFIHead.jpg?t=1351573016

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This assembly has two "pink" first gen drivers side heads. No cracks and I don't have to plug the head for the EGR. With this, no holes are drilled into the exhaust ports. I ported two cracked SPFI heads to get a feel for what to do to these.

Milled012.jpg?t=1350417999

 

I measured the depressions in the exhaust bowl and it's roughly 2mm deep. If I press out the guides, I figure 3 mm removed will clean the exhaust bowls up pretty good. So yea, I've been considering the shortened guide too, and when I get to it, that's what I'll do. I don't think anything bad will happen, and the flow will be substantially improved.

 

Doug

 

That's an awesome shortblock assembly you have there. Maybe the best ea82 block I have ever seen. zzz zzz

  • Like 1
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yeah, these heads have tons of room to improve. i, myself, by just cleaning up the HLA bump, the ridge by the valve seats, and rounding the short turn radius out a bit, and like quidam said, getting into the exhaust bowl a tiny bit. i got a few MPG increase (3-5mpg) and a significant HP and torque increase.

 

has anyone tried that trick of putting a groove on the flat part of the combustion chamber like they do on V-block heads? its supposed to guide the air/fuel mix to the spark plug for more complete ignition.

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yeah, these heads have tons of room to improve. i, myself, by just cleaning up the HLA bump, the ridge by the valve seats, and rounding the short turn radius out a bit, and like quidam said, getting into the exhaust bowl a tiny bit. i got a few MPG increase (3-5mpg) and a significant HP and torque increase.

 

 

I think Miles did some groove work with a skilsawzzz

 

I'll say this again and please correct it if it's wrong. From Chiltons. The XT MPFI made 94 and 97 depending on the year. The '90 SPFI made 90 hp. XT has longer duration cams, moved the power band up a bit.

 

Those heads need a full port to get anything out of them. These intake bowls need hardly any work. There isn't an abundance of "meat" in them, like a typical cast iron old chevy. I don't see how you could make the flow over the valve any better. Just a good cleanup. Hope that makes sense.

 

I laid out some work to do today for tomorrow. Carbide burr and tootsie roll work.

 

Doug

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  • 1 year later...

Hello, I have a question on porting. I have a 97 imp obs ej22 and want to rebuild the engine. As for the heads I want to port them and add some delta cams. I have the option of using the 97 heads, or go with some ej22 heads from a 90 laegacy. This thread seems to have some knowlegable members. Any info/opinions would be appreciated.

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I've got a new EJ22 head here marked out for port work. I'm just going to clean up where the factory left off, primarily above and below where the valve seats are installed.

 

There are sharp ridges around the exhaust valve seats that need smoothed out. That's on the combustion chamber side, smoothed out without taking much material away, which would lower the CR.

 

A good clean up in the bowls, cut away any aluminum left protruding into the port from the valve seat install.

 

The protrusions from the spark plug access tubes in the intake ports can be shaved down a little.

 

Well, that's a start.

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Hello, I have a question on porting. I have a 97 imp obs ej22 and want to rebuild the engine. As for the heads I want to port them and add some delta cams. I have the option of using the 97 heads, or go with some ej22 heads from a 90 laegacy. This thread seems to have some knowlegable members. Any info/opinions would be appreciated.

 

Which heads are in the best shape? I like the dual ports and Subaru seems to go back and forth on this, weather or not to use part of the head for an exhaust manifold. I like a port for each cylinder.

 

Had some time today and worked on the head, which I'll need to duplicate. NOS EJ22 Dual Port, SOHC. I got to thinking, there is a reason head porting is so pricey!

 

Being cautious as I don't want to ruin this head, I took hand in glove with some eighty/ hundred worn carbide paper. I had marked out areas prior and at the end of the day, what this head needs most is a pocket port. If you put your thumb in the exhaust port from the combustion chamber side, and the next finger in the intake port, those pockets.

 

I took some pics today, dead battery. I ended up going over the combustion chamber and all the ports by hand. Took off sharp edges and such.

 

The intake port on the other side from the pocket, the short side radiass Is pretty clean and a strait shot before the vavle. I did take the sharp edge of there tho.

 

I have tootsie rolls and I get a chance I'll do some more. I'm thinking I'd like to ball hone some of these port at a certain point. I use a tub of hotter soapy water and submerge the head in the tub. With a cordless drill.

 

I'm thinking enlarge the exhaust ports by an eight inch or so and see how it looks.

 

Doug

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Which heads are in the best shape? I like the dual ports and Subaru seems to go back and forth on this, weather or not to use part of the head for an exhaust manifold. I like a port for each cylinder.

 

Had some time today and worked on the head, which I'll need to duplicate. NOS EJ22 Dual Port, SOHC. I got to thinking, there is a reason head porting is so pricey!

 

Being cautious as I don't want to ruin this head, I took hand in glove with some eighty/ hundred worn carbide paper. I had marked out areas prior and at the end of the day, what this head needs most is a pocket port. If you put your thumb in the exhaust port from the combustion chamber side, and the next finger in the intake port, those pockets.

 

I took some pics today, dead battery. I ended up going over the combustion chamber and all the ports by hand. Took off sharp edges and such.

 

The intake port on the other side from the pocket, the short side radiass Is pretty clean and a strait shot before the vavle. I did take the sharp edge of there tho.

 

I have tootsie rolls and I get a chance I'll do some more. I'm thinking I'd like to ball hone some of these port at a certain point. I use a tub of hotter soapy water and submerge the head in the tub. With a cordless drill.

 

I'm thinking enlarge the exhaust ports by an eight inch or so and see how it looks.

 

Doug

Please post pics as I am in the middle of trying to get this very thing started on my engine build  thanks.

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P1030249_zps328dfdf7.jpg?t=1387037154

 

After I went over it by hand I marked the low hanging fruit in red. Might be all some would want and it would help flow.

 

Here's an EF12e Subie I did. EJ shares a lot with this head, different shapes though, of course. A lot of what I did to this, I'd do to EJ.

 

JustyIntakePort-EF-12e.jpg

Intake ports. This head isn't gasket matched, but port to port.

 

Exhaust port.

EF-12ExhaustPort.jpg

 

EF12 lower intake.

JustyMPFIIntakeManifold.jpg

 

 

The other end.

SubaruJustyIntakeManifoldPortWork.jpg

 

Upper intake.

SubaruJustyPortandPolish_zpsd67aeade.jpg

 

SubaruJustyEF12eCombustionChamber.jpg

 

EF-12eIntakePorts.jpg

Edited by Quidam
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I "Ported Me Head" today. Went well, about three hours more for this second round. Still going slow and learning this head, but I think I've got it. Would be interesting to have it put on a flow bench when I'm done. The dog leg exhaust port is the hardest and longest port to do. Next head I use the carbide burr first because I'll know what I'm doing, just slugged it out with the sanding tootsie rolls today. I'm going to press the guides out to do a proper full port. Don't have any pics but I'll get some soon.

 

Here is a pro port job on an EJ and I've studied their work and it's deceptive just looking at it. Head Games did this one I believe.

SubaruEJIntakePort_zpse02e030c.jpg?t=138

 

I do think a single exhaust port would be harder to port and this stuff isn't for everyone or their wallet. But there is power to be had in there, you just need to go get it. These things are a breeze to work on after grinding cast iron heads in a previous life.

 

Doug

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