legacycentral bbs

SO i really want to swap some better heads on to my car. Actually I am hoping some new heads would give better power under the curve, and the added flow on top will be a bonus.

anyway which heads should i get. This is also How I am going to have to wire my car, and I plan on getting a stand alone like a Hydra, Autronic, or a haltech.


SO lets see if I have this right, please add info that you know of as well.

Ej20G Heads: easy to find cheap. Bigger ports than the 22t and similar to Ej25 heads. Have all lines for turbo oil and coolant.

Ej25: 2 options sohc & Dohc. Similar flow to eachother. better flow than most heads (22t, ej205, etc) No lines but dohc can be machined easily. sohc has to have exhaust moved a little.

Ej20K heads: big ports, can fit manifold that allows newer turbo inlet. Harder to find.

Thats All i really know. I know the newer heads are going to be an even bigger pain as far as wiring, but more options as far as Engine management.

So fix where I am full of shit and fill me in on the info that I am missing so I can make a better decision.

Its really about what you want and what you want to spend.
EJ20g
If you are on a tight budget, the legacy "g" heads are nice. However they do have hydrolic lash adjusters. These can be noisy and annoying sometimes. Also the compresion ratio may be lower than you want, unless you plan on custum pistons.
EJ25
The dohc are a relativly easy swap. And they can be found reasonably priced. Also, replacement parts are easy to get because they are domestic. A great perk is that you can get early STi and JUN cams and springs for them.
EJ20k
If you can find and afford them, go for it.

Just my two cents

Ok so what about the new legacy 2.5 turbo heads?

I 'm not saying what happened on my lunch hour, or anything else till they are in my hands.

But whats are thoughts on those

Gonna be the same problems as using WRX or STI heads, the cam triggers. But if you go stand alone, I imagine it will be easier to fix than if you are using factory sensors and electronics...

oohohohohohhoohohoho acvs..................

SO I got heads just after I posted this.

Not without difficuties but hey what isnt!!!
Anyway they are new heads off of a 2005 Legacy turbo. Thats right ACVS!!!!!
There is some combustion chamber damage and a few parts here and there.

So does anyone know of a way to fix the combustion chambers? Its not so much in the chamber itself, more on the sides. I am going to see if I can get it buffed out, then maybe ceramic coat the chambers, since I found some one who will do it. Then I need an intake manifold (DZX STill have that one?) and rewire my car. from there I have to decide Autronic or hydra. Definately going to need your guys help on this one!!!!!

the subarus that run with the coilpack direct on the plug wires, you got to change the cam sprokects to ones that run with coilpack in the middle of the intake manifold. with this set up your stock ecu will run PERFECTO.

with avcs i have no clue but all the holes are so small and intake manifold holes are small and dont look worth this crazy set up problem.

I would have just got EJ20G or EJ205 heads and called it a day.

That or better yet, the EJ25 SOHC heads, they flow better anyways and would need less work to use them then the avcs heads you picked up.

Just my .02

but not at the price I got these for!!! that makes everything else worth it. besides we will see if we can make some cool power everywhere with the acvs.

But what will you have into them after you fix the damage? Will they then be as good of a deal still?

1)sell heads
2)buy EJ25 SOHC heads
3)?
4)profit


(bringing back an overused oldie but a goodie there)

if you got a sweet deal on them then selling them and making more money might be a good plan, especially when you consider the AVCS and the potential need for standalone, unless that isn't the plan... although I think there is some way to get AVCS to default to like high lift or something w/o management, check NASIOC

I have the 2004 wrx intake manifold.

the cool think that those heads have

1.there turbo heads and the guts of them are for turbo.

2.they have the oil line and rad line for the turbo so thats easy.

3.they got 2 nipple's on vavle covers for the intake and for the center nipple so it will work like stock PCV system.

bad thing is avcs, becuse you might need stand alone. or not a bad thing becuse its a project.

i no in my greddy emanage i can controle some type of vavle controler system, so a emanage might work with stock ecu and emanage running for vavle controler.

last thing is there is crazy oil lines every where for the avcs, i got a sti total apart right now and is there ever oil lines for that avcs shit.

so let me get this straight. ej20k heads are from JDM WRX's?

^^ YES.

A stand alone was the plan, remember that I am running the 22t on the 1.8 ecu with a perfect power and the setup pretty much sucks. I ahave been wanting to go to a stand alone for a while but my heads/ignition/wiring has been holding me back from that. it is gonna cost me, but the car should be super reliable, and powerful so hopefully I wont have to worry about much. Besides someone was wanting to try acvs in some other thread on here. Send the newbie in to do it.

AVCS is NOT a performance enhancer, it's an emissions control device. Sure, you can tweak it a little bit to make some power, but a properly tuned car with non-AVCS heads will make plenty of power with a wide torque if set up properly.

Did you get cam gears with them? Timing belt covers? Intake manifold? fuel rails? Vacuum plumbing? etc. etc. Core heads in need of repairs without all the ancillaries will add up really quickly. If it were me, I would dump them and buy something else.

I would still like to see them, however. So bring one of them down on Sunday if you can

Well if we are not seeing any performance from the acvs? I can run the car without them with no ill effects correct?

Yes, you can not use AVCS.

AVCS is only helpful if you know how to use it to your advantage. Not many do.

please explain both statements Bac 5.2

AVCS is just the same as VVTi, VANOS and all the other variable cam setups. Oil pressure is controlled by a solenoid which moves the intake cam. I'm pretty sure AVCS can move up to 35 degrees. You need to be able to adjust the fixed point in order to get the most out of it on a modified engine. After that, it's just like adjusting cam gears. Advancing the gear (increasing the solenoid duty cycle) increases overlap. Retarding the gear (shutting off the solenoid) reduces overlap and makes the IVC event happen later.

oh... whatever you're looking at to control it, it needs to be compatable with a variable pressure oil solinoid like VVTi and VANOS have. VTEC works diffrently so a VTEC controller won't work for AVCS.

You can leave AVCS disconnected, and it will behave as if you... don't have AVCS. The black WRX in Import Tuner a few months ago has a JDM Forester motor, with AVCS disabled.

With AVCS you can tune it to increase overlap to allow exhaust gas to help cool the combustion chamber, thus helping to prevent det.

Junior is right.