I Got Gen 3 Heads!!!!!!

[NuclearBacon]

there it was.... sitting in the junkyard... sitting with 104,000 miles.... pushbutton 4WD .....

 

and gen 3 heads....

 

when i pulled them, they both had hairline cracks between the ports.

my question is where could i take these to get completly re-worked? 3 angle valve job, perhaps sodium filled valves, something like that.

 

i've heard of delta cams, and that CCR place on the forums front, but does anyone have experience with a complete rebuild for the heads? i thought it would be a cool thing to have for my future shortblock

 

thanks!

[john in KY]

[quote name=NuclearBacon perhaps sodium filled valves, something like that.

 

QUOTE]

 

 

Never happen. Ford used them in the hi-po 427 and Super Duty trucks back in the 60s.

[GeneralDisorder]

perhaps sodium filled valves, something like that.

 

Not only would that not help at all, but it might contribute to the exhaust port cracking common to these heads.

 

Plus it would cost a bloody fortune! You have any idea what sodium filled valves cost?

 

GD

[NuclearBacon]

one million dollars.....

 

so that aside...... any ideas??

 

can i go to my local machine shop to work on the heads? or do they not do subaru...

[MilesFox]

there it was.... sitting in the junkyard... sitting with 104,000 miles.... pushbutton 4WD .....

 

and gen 3 heads....

 

when i pulled them, they both had hairline cracks between the ports.

my question is where could i take these to get completly re-worked? 3 angle valve job, perhaps sodium filled valves, something like that.

 

i've heard of delta cams, and that CCR place on the forums front, but does anyone have experience with a complete rebuild for the heads? i thought it would be a cool thing to have for my future shortblock

 

thanks!

not entirely necessary. it is common for the cracks to be between the valves and even go down to the valve guide.

 

only be aware of cracks inside the exhaust port, where it goes to the water jacket

 

my rx had cracks between the valves down to the valve guides. i ported them with a dremel and they have been just fine

[joostvdw]

what is so special about these heads? As far as I know, they are "less prone" to cracking (re-design? tempered?) and were only fitted as replacement instead of stock on a car.

[archemitis]

stainless steel valves are the ticket these days and you can get them from alot of sources, but i dont think you need them unless your building it to run high RPMS, like 7k RPMS, which if its a turbo motor, i guess thats the idea

 

if it were me, id get the high perf stainless valves and heavy springs from *insert favorite company name here*, then take a dremel to them, then have a local head shop fit everything together. while your at it have somebody weld up the egr passage on the one side so that port doesnt suffer any extra turbulence.

grinding on aluminum is fun, just practice on a spare set, and dont go hog wild on them. check out that "splitting headache" shows you where you need to remove metal, and where you just smooth it out.

on na engines heads, and the right cam make all the difference in the world. on a turbo motor, it helps, but so does booost!

[joostvdw]

I cannot quote a sourse, but I recall that the stock cams are the best on turbo engines...

 

hi torque doesn't give enough flow at higher rpm (usually where the turbo kicks in) and hi rpms loose lots of torque at the bottom end and help in the top end but the turbo is already there, so the added bonus of the cams is barely noticeable

 

stock cam is a nice mid-way solution, only thing that might help is increased lift, but that's not possible on the EA heads.

 

again, just heresay, correct me if I'm wrong.

[beataru]

Anything is possible on any motor, it just requires money and alot of it. I dont know if your local machine shop could do everything, why not just go in there and ask them. Theres a machine shop right by my house that my bro in law took his RS heads to and they assembled the brian crower this and titanium that. Anyways, I dont know where exactly to take them to get them welded up but a machine shop guru should know.

[daeron]

just putting things into perspective...

 

1.8 liter motor, wanting 250 horses. 138 8/9 hp/liter there. multiply that out, for a 5.8 liter motor and you're at 800 horsepower.

 

 

Think you can do as good a job at nursing horses out of displacement as NASCAR engineers with billion dollar budgets?

 

I am all for setting enthusiastic goals, but it takes a hell of a build to pull 200 horses out of 2 liters, with a WELL designed engine, and subaru built these engines for economy. Shoot as high as you can, but don't be sad when you don't reach your lofty goal.

 

Unless you WANT to spend money figuring out ways to make this ultra high comp, beautiful squishing, perfectly shaped combustion chamber, miraculously rework the intake and exhaust ports, (IF theres enough aluminum to do all that work, and the right person to find just the right combination of shapes and flows) complete (of course) with the matching dished piston to *just* give you the right shape, and maybe convert over to LPG to run higher static CR than you could with gasoline, and get the devil's own turbocharging system on it... naturally Oring the block etc, maybe even bore out as much as possible (if any) and somehow magically keep it all glued together..... but that list is just the barest beginnings of what would be needed. The engine management alone would cost 1500 dollars, and then someone has to tune it on a dyno before it makes its value shown...I would LOVE to see it. Hordes of us would. But I ain't holding my breath.

 

Besides, 140 horsepower is alot more fun than it sounds like. 170, even moreso. It isn't "settling" for less when its about all you can handle anyhow

[WoodsWagon]

but it takes a hell of a build to pull 200 horses out of 2 liters, with a WELL designed engine,

 

Wrx engine= 2.0l

Horsepower (stock)= 227

 

They get modded from there.

 

The problem with EA engines is that they are missing 8 valves. And 2 main bearings. And an aftermarket. Plus the bathtub head isn't exacly a performance design.

[worknwood]

Try "Terrell's" (not sure of spelling) in Chico, they are near the tracks and south of the train Depot a few blocks. I'm away from my records and don't have the address. I had a head for my 88 RX rebuilt there and was very pleased with their work. The head had spit a valve seat that chewed thing up pritty good, plus there was the typical crack between the ports. They specialize in head rebuilding and may have answers to your other questions.

[daeron]

Wrx engine= 2.0l

Horsepower (stock)= 227

 

They get modded from there.

 

The problem with EA engines is that they are missing 8 valves. And 2 main bearings. And an aftermarket. Plus the bathtub head isn't exacly a performance design.

my apologies, i had in mind older 2.0 liter engines.... I don't dabble that much in cars with less than two decades on 'em, so I forgot to mention the old skool vs new school CC/valve configuration exclusion... In reality there is ALOT more to the heads of the WRX engine than simply two more valves, the entire dynamic flow pattern of the gasses through the intake/cylineder/exhaust tract is RADICALLY different.

 

One of the difference I had in mind earlier when making the post, in regards to CC design, can be illustrated here.. These are two photos of an L28ET (Nissan Turbo 280ZX) P90 cylinder head. The first combustion chamber is stock (stock-ish, the heads been worked, but not much radical change was made in the combustion chamber. Apologies, I lack a picture of a bone stock P-90 head.) and the second is a redesign along the lines of what I had in mind. The redesign reflects the flow pattern changes I mentioned, and also the redesign is a rough mock up, on a welded "test" head, to see how well the CC design that the builder had in mind would function (,echanically) on an actual shortblock on a stand..

 

 

 

Note the change of spark plug angle on the "worked" head versus the relatively stock one.

 

ALSO, for the record, this combustion chamber is the one that REALLY seals the deal on my perceived "similarities" between the EA heads and the Nissan heads.. A pic of a stock head would make it clearer. (the "stockish" image above has had some serious work to it to make a minimal APPEARING, yet significant change in the performance; the bone stock CC is much more like the EA82 one.) Although the shape is somewhat different, when you look at them firsthand there is a distinct similarity between them, and the CC of the OLDER L-series heads was even more like in shape to the EA82, but it was an open-deck engine, which means that the CC was not just the shape it assumed, but also a small amount of the entire cylinder head firing deck.. In other words, there is a "bore" on the cylinder head that corresponds to the bore of the cylinder, in addition to the distinctive shape of the recess in the head that the valves reside in. The stock older Datsun heads have a "recess" that looks identical to the EA82 CC, and I HAVE seen more than two engines in pieces.

[NuclearBacon]

wow.....

 

....wow!

 

ok, i'm looking at an additional 30 horse over stock. like and not expecting to get there!

 

also any specifics on the Gen 3 difference? ...wow what a thread!

[archemitis]

my apologies, i had in mind older 2.0 liter engines.... I don't dabble that much in cars with less than two decades on 'em, so I forgot to mention the old skool vs new school CC/valve configuration exclusion... In reality there is ALOT more to the heads of the WRX engine than simply two more valves, the entire dynamic flow pattern of the gasses through the intake/cylineder/exhaust tract is RADICALLY different.

 

One of the difference I had in mind earlier when making the post, in regards to CC design, can be illustrated here.. These are two photos of an L28ET (Nissan Turbo 280ZX) P90 cylinder head. The first combustion chamber is stock (stock-ish, the heads been worked, but not much radical change was made in the combustion chamber. Apologies, I lack a picture of a bone stock P-90 head.) and the second is a redesign along the lines of what I had in mind. The redesign reflects the flow pattern changes I mentioned, and also the redesign is a rough mock up, on a welded "test" head, to see how well the CC design that the builder had in mind would function (,echanically) on an actual shortblock on a stand..

 

 

 

Note the change of spark plug angle on the "worked" head versus the relatively stock one.

 

ALSO, for the record, this combustion chamber is the one that REALLY seals the deal on my perceived "similarities" between the EA heads and the Nissan heads.. A pic of a stock head would make it clearer. (the "stockish" image above has had some serious work to it to make a minimal APPEARING, yet significant change in the performance; the bone stock CC is much more like the EA82 one.) Although the shape is somewhat different, when you look at them firsthand there is a distinct similarity between them, and the CC of the OLDER L-series heads was even more like in shape to the EA82, but it was an open-deck engine, which means that the CC was not just the shape it assumed, but also a small amount of the entire cylinder head firing deck.. In other words, there is a "bore" on the cylinder head that corresponds to the bore of the cylinder, in addition to the distinctive shape of the recess in the head that the valves reside in. The stock older Datsun heads have a "recess" that looks identical to the EA82 CC, and I HAVE seen more than two engines in pieces.

 

that stockish head has oversized seats pressed in, and the intake seat is even machined into the exhaust seat! thats super cool.

that gives me a realy good idea, since the valves are both pointing in the same direction, you can go way bigger on the valves than you could on a hemispherical combustion chamber, since the valves dont point at eachother, you can go super big!

[discopotato03]

I'm really curious to know why EA82T heads crack between the valve seats and suspect its elevated EGT's because of the "EGR" pipe acting as a header pipe .

 

I'm not sure if anyone in the US has tried thermal barrier coating the chambers/exhaust ports/exhaust valve heads but it may help with the cracking issue . Really have to do better than the std header I think before much effort is put into porting or larger valves . After that if reliable larger exhaust valves would be the next upgrade I think .

 

I've only seen one P90 head and It had deeper more open chambers that a regular L28 Nissan . We had over here a pre emmission spec L24E head with more prounounced heart shaped chambers like a SSS L16 or L18 (219 castings were best L4 heads) . Anyhow the pre smog L24 head IMO is a better basis for a turbo one because the chambers are more compact and have more squish/quench area . Obviously more piston dish is required to get the desired static CR . I say better because they require no welding which is a bonus to any head casting .

The thing with L28 ET engines was that they are also designed around low static CR (I think 7.7 as well) and cammed to suit low compression pressure at low revs . I would much prefer up around 8.5 - 9:1 static CR and a mild N/A cam profile . It means you have to make the effort to improve the exhaust manifold/hot side of turbo so that restriction/reversion don't set in and have it detonate to death .

My EA82T build will be along these lines (NA pistons/cams/better header and turbo) . If I can thermal barrier coat everything that see's fire then they shouldn't cop the thermal thrashing normally seen in turbo engines .

 

I was very lucky to be given a set of EA82T heads that haven't cracked but I don't have any clue as to which generation they are . Sorry if its been asked 1001 times but how can I identify G1-2-3 heads .

 

Also thanks for the heads up with Harley sized valves , I'm interested in larger exhaust valves and come fron a Nissan L20B/FJ20ET background . Also you may or may not know that Nissan had a large financial stake in Subaru back in the 80's so some same/similar components are out there .

 

Cheers Adrian .

[daeron]

The turbo Z-car motors lowered their compression ratio through use of dished pistons; the NA cars had identical CC's on their heads and ran i think 8.5 or 8.8:1. IF, you take the P90 head you mentioned, shave it .080", and throw it on a stock L28 with (late) stock flattop pistons, you wind up in the 10.5: compression ratio range. The early L24 head (casting E31 as opposed to the far more common e88 L24 head) had a combustion chamber shaped and sized almost identical to the P90/79/90A and the Maxima N47 heads. Read: P79/90/90A are all three identical CCs, E31 and N47 from maxima were both very very similar.

 

The Datsun L-series used so many different kinds and shapes of pistons and combustion chambers that there ARE no set and solid rules, and almost anything can be built in a permutation of stock parts. Honestly, if it weren't for the ABSURDLY huge bore on our boxer engines, ALOT of bits would likely be transferable from various datsuns to the subaru world. I have thought long and hard about simply installing an EA82 SPFI system onto one of my uncle's datsun roadsters for fuel economy, and I may be wrong, but I think the greatest difficulty would lie in assembling a distributor from datsun parts and subaru parts that would run the thing. I doubt it would be WORTH messing with, since one could achieve both fuel economy and good power using subaru components controlled by Megasquirt.. BUT, I bet I could do it and make it run surprisingly well.

 

You say hit-atchee, I say hit-otchee, right?

 

Not sure if anything in this post was really relevant to the subaru world, but consider it a clarification of my last post

[Gloyale]

I'm really curious to know why EA82T heads crack between the valve seats and suspect its elevated EGT's because of the "EGR" pipe acting as a header pipe .

I doubt that the header(crossover/uppipe) is the reason for those cracks. BTV cracks are almost a garauntee for any EA82 suby heads, turbo or not.

 

 

I was very lucky to be given a set of EA82T heads that haven't cracked but I don't have any clue as to which generation they are . Sorry if its been asked 1001 times but how can I identify G1-2-3 heads .

 

Look at the cating on the bottom of the head

 

EA82 = Gen 1

 

EA82 = Gen 2

 

EA82 surrounded by a full border= Gen 3

[discopotato03]

Thanks for that but just to be sure what is the "cating"

 

Cheers and thanks , Adrian .

[joostvdw]

Thanks for that but just to be sure what is the "cating"

 

Cheers and thanks , Adrian .

 

he ment casting, look at the underside of the head (the exhaust side) and you will see the different styles of "EA82" cast into the head.

[Gloyale]

Thanks for that but just to be sure what is the "cating"

 

Cheers and thanks , Adrian .

 

Yeah I meant casting. I just moved cross country, and when we unpacked the only keyboard we could find was this old one with the sticky "S" key. You may have noticed alot of missing "S"s in my pots.